The high protein vegetables that actually deliver are legumes: a cup of cooked soybeans has about 31 grams of protein, and a cup of lentils about 18.
Ordinary vegetables are far lower. Even the best of them, cooked spinach and sweet corn, give roughly 5 grams per cup.
So if you want plants to carry real protein, beans, lentils, peas and soy do the heavy lifting.
Every figure below comes from USDA FoodData Central, the U.S. Department of Agriculture’s nutrient database, for foods cooked the way most people eat them.
Legumes carry the category, most vegetables do not
Legumes are the seeds of pod plants: beans, lentils, chickpeas, peas and soybeans.
Cooked beans, lentils, chickpeas and soybeans hold 8.67 to 18.21 grams of protein per 100 grams in the USDA data, and green peas 5.15. Green vegetables sit at about 2 to 3 grams.
That gap explains why lists of “high protein vegetables” so often lean on beans and edamame. Take legumes out, and no vegetable in the table below reaches 6 grams per typical serving.
Video: Trinity Health Michigan
Protein per cooked serving, ranked
The table lists each food at the serving size USDA itself publishes, plus the value per 100 grams so you can compare foods fairly.
| Food (cooked) | Group | USDA serving | Protein per serving | Protein per 100 g |
|---|---|---|---|---|
| Soybeans, mature, boiled | Legume | 1 cup (172 g) | 31.3 g | 18.21 g |
| Edamame, frozen, prepared | Legume | 1 cup (155 g) | 18.5 g | 11.91 g |
| Lentils, boiled | Legume | 1 cup (198 g) | 17.9 g | 9.02 g |
| Kidney beans, boiled | Legume | 1 cup (177 g) | 15.3 g | 8.67 g |
| Black beans, boiled | Legume | 1 cup (172 g) | 15.2 g | 8.86 g |
| Chickpeas, boiled | Legume | 1 cup (164 g) | 14.5 g | 8.86 g |
| Spinach, boiled, drained | Vegetable | 1 cup (180 g) | 5.3 g | 2.97 g |
| Sweet corn, yellow, boiled | Vegetable | 1 cup cut (149 g) | 5.1 g | 3.41 g |
| Potato, baked, with skin | Vegetable | 1 medium (173 g) | 4.3 g | 2.50 g |
| Green peas, frozen, boiled | Legume | 1/2 cup (80 g) | 4.1 g | 5.15 g |
| Kale, boiled, drained | Vegetable | 1 cup (118 g) | 3.5 g | 2.94 g |
| Artichoke, globe, boiled | Vegetable | 1 medium (120 g) | 3.5 g | 2.89 g |
| White mushrooms, boiled | Vegetable | 1 cup pieces (156 g) | 3.4 g | 2.17 g |
| Asparagus, boiled | Vegetable | 1/2 cup (90 g) | 2.2 g | 2.40 g |
| Brussels sprouts, boiled | Vegetable | 1/2 cup (78 g) | 2.0 g | 2.55 g |
| Broccoli, boiled, chopped | Vegetable | 1/2 cup (78 g) | 1.9 g | 2.38 g |
| Cauliflower, boiled | Vegetable | 1/2 cup (62 g) | 1.1 g | 1.84 g |
| For scale: egg, hard-boiled | Reference | 1 large (50 g) | 6.3 g | 12.58 g |
Source: USDA FoodData Central, SR Legacy, boiled without salt unless noted. Protein per serving is the per-100 g value times the USDA portion weight, rounded to one decimal. Checked November 9, 2026.
FDC IDs: 174271, 168411, 172421, 173740, 173735, 173757, 168463, 169999, 170093, 170017, 169238, 168386, 169252, 168390, 169971, 169967, 170397, 173424.
Compare the per 100 g column, not the serving column. A half cup of green peas looks weaker than a cup of spinach, yet per 100 grams peas carry 5.15 grams of protein and cooked spinach 2.97.
If you want to see how an egg compares in more detail, we break it down by size in how many grams of protein in an egg.
The spinach trap: raw versus cooked
Spinach is the vegetable most often called high in protein, and the USDA numbers show why that claim misleads. A cup of raw spinach weighs 30 grams and has about 0.9 grams of protein.
A cup of boiled spinach weighs 180 grams, because cooking collapses the leaves. That cup holds about 5.3 grams. Per 100 grams the two are almost the same, 2.86 raw versus 2.97 cooked.
Cooking packs about six cups of raw leaves into one cup. A spinach salad gives you much less protein than the “high protein” headlines suggest.
Edamame and mature soybeans are not the same food
Edamame are young soybeans picked green. Mature soybeans are the dried beans, boiled. USDA lists edamame at 11.91 grams of protein per 100 grams and boiled mature soybeans at 18.21.
Per cup, that is about 18.5 grams for edamame and 31.3 for soybeans. Both are good sources; just do not assume a bowl of edamame matches a cup of cooked soybeans.
What a vegetable-only plate really adds up to
Using the table, one cup of cooked spinach, one cup of corn, a medium baked potato with skin and half a cup of broccoli give about 16.6 grams of protein together.
A single cup of cooked lentils gives about 17.9 grams. Four servings of vegetables roughly equal one serving of lentils, which is the clearest way to see where plant protein comes from.
How much you need depends on your body weight and situation. We walk through the official reference values in how many grams of protein a day.
Where to add legumes first
- Add one legume to each main meal: lentils in soup, chickpeas in a salad, black beans in a wrap.
- Choose peas, corn and potatoes as your starchy sides; they beat most green vegetables on protein per serving.
- Count cooked greens by the cooked cup, not by the raw bag, when you track intake.
- Keep frozen edamame in the freezer as a ready side dish.
The cooking fat matters for the rest of the meal, not the protein. If you are unsure which oil to use for beans and greens, see what are seed oils.
Tomato-based bean dishes are a common pairing, and we cover the inflammation question in do tomatoes cause inflammation.
Why your numbers may differ from a label
USDA values are averages from lab analyses. Variety, growing conditions, cooking time and how much water the food absorbs all shift the protein per cup.
Treat the table as a reliable guide to ranking, and use the package label for a specific product.
If you have a health condition that affects how much protein you should eat, check with your doctor or a registered dietitian before changing your diet.
Frequently asked questions
Which vegetable has the most protein?
Among legumes, cooked mature soybeans lead the USDA data at about 31 grams per cup. Among non-legume vegetables in our table, cooked spinach and sweet corn are highest per cup, at roughly 5 grams each. Per 100 grams, boiled spinach has 2.97 grams and sweet corn 3.41, so the cup size drives the gap.
Is broccoli high in protein?
Not by serving size. USDA lists half a cup of boiled, chopped broccoli at about 1.9 grams of protein, while a cup of cooked lentils gives about 17.9 grams, roughly nine times as much. Broccoli brings fiber and other nutrients, but it will not cover much of your daily protein.
Are peas a vegetable or a legume?
Green peas are legumes botanically, and they behave like one on protein: 5.15 grams per 100 grams cooked in USDA data, nearly double most green vegetables. A half cup of frozen, boiled peas gives about 4.1 grams.
