Our pick. Ito En
Check priceOi Ocha Green Tea Review: Which Ito En Oi Ocha Is Best?
Ito En's Oi Ocha line, bottle by bottle and bag by bag: what is in each one, the caffeine Ito En publishes, the Bold vs original difference, and the cheapest way to buy it.
By Justin Park~8 min readUpdated 2026-09-24
Our top pick.Best Oi Ocha overall
Ito En Oi Ocha Unsweetened Green Tea, 16.9 oz (Pack of 12)
- Price.
- $18.78 at time of writing (12 bottles, about $1.57 each)
- Our rating.
- 4.6 out of 5
The original: Japanese green tea, water, and vitamin C, with nothing sweet added.
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Ito En Oi Ocha is a good, genuinely unsweetened Japanese green tea, and the best Oi Ocha for most people is the original Oi Ocha Unsweetened Green Tea in the 16.9 oz bottle: just water, green tea, and vitamin C, about 60 mg of caffeine per bottle, and roughly $1.57 a bottle in a 12-pack at time of writing. If you want a stronger, more bitter cup, Oi Ocha Bold has about 100 mg of caffeine per bottle; if you brew at home, the Oi Ocha tea bags are the cheapest way in.
Oi Ocha is Ito En's flagship green tea brand, and Ito En calls it Japan's number one green tea brand. The bottles are brewed from Japanese green tea leaves rather than powder or concentrate, according to Ito En's Amazon listings, and contain no sugar or sweeteners. Below, each Oi Ocha product is laid out with Ito En's own ingredient and caffeine figures, so you can pick the right one. For the wider Ito En range, including sencha shots and hojicha, see our Ito En tea review. We are reader-supported and may earn a commission through our links.
The short version.
- Best Oi Ocha overall: the original Unsweetened Green Tea, 16.9 oz: green tea, water, vitamin C, zero sugar.
- Caffeine: about 60 mg per 16.9 oz bottle for the original, Organic, Matcha Genmaicha, and Hojicha bottles; about 100 mg for Bold (itoen.com).
- Bold vs original: Bold is brewed stronger, with at least 400 mg of catechins per bottle per Ito En, and more caffeine.
- Cheapest per cup: Oi Ocha tea bags, 40 count, about 29 cents a bag at time of writing.
- Organic: an Organic Oi Ocha bottle exists at about the same price as the original.
- Calories: the unsweetened bottles are listed at 5 calories each.
| Oi Ocha | What is in it | Caffeine | Price |
|---|---|---|---|
| Unsweetened Green Tea, 16.9 oz | Water, green tea, vitamin C | ~60 mg / bottle | $18.78 / 12 |
| Bold Green Tea, 16.9 oz | Stronger brew; 400 mg+ catechins | ~100 mg / bottle | $18.85 / 12 |
| Organic Green Tea, 16.9 oz | Water, organic green tea, vitamin C | ~60 mg / bottle | $18.87 / 12 |
| Matcha Genmaicha, 16.9 oz | Green tea, roasted rice, matcha | ~60 mg / bottle | $26.39 / 12 |
| Oi Ocha Green Tea Bags | Japanese green tea, made in Japan | Not published; green tea ~28 mg / 8 oz (USDA) | $11.56 / 40 |
The Oi Ocha line on Amazon, September 2026. Caffeine per Ito En; prices at time of writing.
Ito En Oi Ocha Unsweetened Green Tea, 16.9 oz (Pack of 12)
Ito En
The original: Japanese green tea, water, and vitamin C, with nothing sweet added.
Bottom line: The reference Oi Ocha and the one to buy first. A clean, dry, unsweetened green tea with a short ingredient list, at about $1.57 a bottle in the 12-pack.
Origin and grade. Ingredients per Ito En: purified water, green tea, ascorbic acid (vitamin C). About 60 mg caffeine per bottle.
The original Oi Ocha is what most people mean by the name. Ito En lists three ingredients, purified water, green tea, and vitamin C, and about 60 mg of caffeine per 16.9 oz bottle, which is a little more than a cup of brewed black tea (USDA: about 47 mg per 8 oz) spread over twice the volume. Ito En's Amazon listing says it is brewed from first flush whole green tea leaves grown in Japan, not from powder or concentrate, with no sugar or artificial sweeteners and 5 calories a bottle.
The 12-pack on Amazon brings the price to about $1.57 a bottle at time of writing, against $2.69 for a single bottle on Amazon. Check the 12-pack price on Amazon.
Who should buy it.
Anyone replacing soda or sweet tea with a zero-sugar drink, and fans of Japanese green tea.
What we don't like.
Dry and slightly bitter if you expect sweetness; bottles are bulky to store.
- Type
- Bottled unsweetened green tea
- Caffeine
- About 60 mg per 16.9 oz (Ito En)
- Calories
- 5 per bottle (listing)
- Ingredients
- Water, green tea, vitamin C
What we like.
- Three ingredients, no sugar
- Japanese whole-leaf brew per Ito En
- Cheap per bottle in a 12-pack
Worth noting.
- Dry and bitter for sweet-tea drinkers
- Bulky case
Ito En Oi Ocha Unsweetened Bold Green Tea, 16.9 oz (Pack of 12)
Ito En
A much bolder brew with about 100 mg of caffeine and at least 400 mg of catechins per bottle.
Bottom line: The pick if the original tastes thin to you or you want it as a coffee substitute: Ito En brews it stronger, and it carries about two thirds more caffeine.
Origin and grade. Per Ito En: about 100 mg caffeine and a minimum of 400 mg naturally occurring catechins per 16.9 oz bottle.
Ito En describes Bold as "a brew for those who prefer a much bolder tasting green tea than Oi Ocha". The numbers back that up: about 100 mg of caffeine per bottle versus about 60 mg for the original, and a minimum of 400 mg of catechins, the astringent compounds that give green tea its bite. Expect a more bitter, more intense drink. Check Oi Ocha Bold on Amazon.
Who should buy it.
Strong green tea fans and anyone who wants a coffee-level lift without coffee.
What we don't like.
Too bitter for some; this listing was marked low stock.
- Type
- Bottled unsweetened green tea, strong
- Caffeine
- About 100 mg per 16.9 oz (Ito En)
- Catechins
- 400 mg minimum per bottle
What we like.
- Most caffeine in the line
- Stronger flavor
Worth noting.
- More bitter
- Stock comes and goes
Ito En Oi Ocha Green Tea Bags, 40 Count
Ito En
The same brand as a tea bag, made in Japan, for hot or iced tea at home.
Bottom line: Oi Ocha for a fifth of the bottle price per serving. Brew hot, or brew strong and pour over ice to make your own bottles.
Origin and grade. Made in Japan per the listing; best within 24 months of production.
At about 29 cents a bag, the Oi Ocha bags are the cheapest way to drink the brand. Ito En does not publish a caffeine number for the bags; USDA FoodData Central puts a cup of brewed green tea at about 28 mg per 8 oz. Use water well below boiling, around 170 to 180°F, and a short steep of 1 to 2 minutes; our brewing temperature guide explains why green tea turns bitter in boiling water. Check Oi Ocha tea bags on Amazon.
Who should buy it.
Home brewers and anyone who wants Oi Ocha at the lowest cost per cup.
What we don't like.
You do the brewing; no published caffeine figure.
- Type
- Japanese green tea bags
- Caffeine
- Not published; about 28 mg per 8 oz for brewed green tea (USDA)
- Bags
- 40
- Origin
- Made in Japan (listing)
What we like.
- About 29 cents a cup
- Hot or iced
Worth noting.
- Needs cooler water to avoid bitterness
Ito En Organic Oi Ocha Unsweetened Green Tea, 16.9 oz (Pack of 12)
Ito En
The original recipe made with organic green tea, at nearly the same price.
Bottom line: If you prefer organic, there is no real price penalty: the Organic Oi Ocha 12-pack cost about the same as the original at the time of our check.
Origin and grade. Per Ito En: purified water, organic green tea, vitamin C; about 60 mg caffeine per bottle.
Same format, same about-60 mg caffeine, organic leaf. Check Organic Oi Ocha on Amazon.
Who should buy it.
Organic shoppers who want the original Oi Ocha profile.
What we don't like.
Nothing specific beyond the usual bulky case.
- Type
- Bottled organic green tea
- Caffeine
- About 60 mg per 16.9 oz (Ito En)
- Ingredients
- Water, organic green tea, vitamin C
What we like.
- Organic
- Same price as the original
Worth noting.
- Bulky case
Ito En Oi Ocha Unsweetened Matcha Genmaicha, 16.9 oz (Pack of 12)
Ito En
Green tea with roasted rice and matcha for a nuttier, rounder bottle.
Bottom line: The roasted rice gives genmaicha a toasty, savory note that can be easier to like than straight green tea. It costs more per bottle than the original.
Origin and grade. Per Ito En: purified water, roasted rice, green tea, vitamin C, matcha; about 60 mg caffeine per bottle.
Genmaicha is green tea blended with roasted rice, and Ito En adds matcha to this bottle. Caffeine is about the same as the original at roughly 60 mg. If you like it, our best genmaicha guide has loose and bagged options. Check Matcha Genmaicha on Amazon.
Who should buy it.
People who find plain green tea too grassy.
What we don't like.
About $2.20 a bottle.
- Type
- Bottled genmaicha with matcha
- Caffeine
- About 60 mg per 16.9 oz (Ito En)
What we like.
- Toasty, rounder flavor
- No sugar
Worth noting.
- Pricier than the original
What is Oi Ocha?
Oi Ocha is the green tea brand of Ito En, the Japanese tea company. Ito En calls it Japan's number one green tea brand, and its listing translates the name as "tea, please". In the US the line is mostly unsweetened bottled green teas, plus tea bags and powders. The bottles are brewed from Japanese green tea leaves, according to Ito En, rather than made from powder or concentrate, and the core bottles contain no sugar or artificial sweeteners.
Oi Ocha caffeine, bottle by bottle
| Oi Ocha | Caffeine (Ito En) |
|---|---|
| Unsweetened Green Tea, 16.9 oz | about 60 mg |
| Organic Green Tea, 16.9 oz | about 60 mg |
| Matcha Genmaicha, 16.9 oz | about 60 mg |
| Hojicha Roasted Green Tea, 16.9 oz | about 60 mg |
| Bold Green Tea, 16.9 oz | about 100 mg |
For comparison, USDA FoodData Central lists 8 oz of brewed coffee at about 95 mg, so a bottle of Bold is roughly a cup of coffee and a bottle of the original is about two thirds of one. See our caffeine by brand table for how that compares with other teas.
Oi Ocha Bold vs original
The difference is strength. Ito En brews Bold for "a much bolder tasting green tea", with at least 400 mg of catechins and about 100 mg of caffeine per bottle, against about 60 mg for the original. Choose the original for an everyday, refreshing bottle and Bold if the original tastes weak to you or you want the extra caffeine.
Where to buy Oi Ocha for less
A single 16.9 oz bottle was listed on Amazon at $2.69 at the time of our check. The 12-packs worked out to about $1.57 a bottle for the original and Organic at the time of our check, and the 40-count bags to about 29 cents a cup. Ito En also sells a 10.6 oz bottle and a 2 liter bottle for sharing.
Questions, answered.
Ito En green tea review: is it good?
Yes. Ito En's Oi Ocha unsweetened green tea is a clean, sugar-free Japanese green tea with three ingredients (water, green tea, vitamin C) and about 60 mg of caffeine per 16.9 oz bottle. It is dry and slightly bitter rather than sweet, which is the point.
What is the best Oi Ocha?
The original Oi Ocha Unsweetened Green Tea in the 16.9 oz bottle. Pick Oi Ocha Bold if you want a stronger taste and about 100 mg of caffeine, Organic if you prefer organic leaf, Matcha Genmaicha for a toasty flavor, and the Oi Ocha tea bags if you want the lowest cost per cup.
Ito En Oi Ocha tea reviews: what do they say?
Our read: the line's strengths are that it is truly unsweetened, has a short ingredient list, and is brewed from Japanese whole leaves per Ito En. The trade-off is a dry, slightly bitter taste that will surprise anyone used to sweetened bottled tea.
How much caffeine is in Oi Ocha?
About 60 mg per 16.9 oz bottle of the original, Organic, Matcha Genmaicha, and Hojicha, and about 100 mg per bottle of Oi Ocha Bold, according to Ito En.
Does Oi Ocha have sugar?
The unsweetened bottles do not. Ito En lists the original as purified water, green tea, and vitamin C, with no sugar or artificial sweeteners.
Is Oi Ocha the same as Ito En?
Oi Ocha is a brand made by Ito En. Ito En also sells other lines, such as Matcha Love and Sencha Shot.
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