A typical 1 medium serving of apple contains 0.5 grams of protein (0.26 g per 100 g), which makes it only a minor source of protein. That covers roughly 1% of the 50 g reference Daily Value, so it adds toward your protein total for the day.
Only about 2% of the calories in apple come from protein, so it is more of an energy food than a protein food. It is worth eating for other reasons; the protein it adds to a day is incidental.
Among the 71 fruits in the database, apple ranks 63rd by protein per serving, and 774th out of all 796 foods on the site. Set against canned pineapple, another fruit entry in the database, a serving carries about 0.5 g less protein (canned pineapple has 1 g per 1 cup).
It is an incomplete protein on its own; pairing it with other plant foods across the day covers the full range of essential amino acids. The serving above is counted by piece at 182 g. Because pieces vary, the per-100 g figure is the one to use when comparing this against a food measured a different way.
Source: USDA FoodData Central #171688 - "Apples, raw, with skin (Includes foods for USDA's Food Distribution Program)" (SR Legacy, published 4/1/2019). Values are the published reference figures for that record, not lab measurements for a specific brand or batch.
Quick answers
Apple protein FAQ
How much protein is in apple per 100 g?
Apple has 0.26 g of protein per 100 g. A typical 1 medium serving (182 g) provides 0.5 g.
Is apple a complete protein?
No. Apple is an incomplete protein on its own; pairing it with other protein sources across the day covers the full range of essential amino acids.
How much of the Daily Value does a serving of apple cover?
A 1 medium serving of apple contains 0.5 g of protein, about 1% of the 50 g reference Daily Value.
Is apple a good source of protein?
Apple is only a minor source of protein, and about 2% of its calories come from protein, which makes it more of an energy food than a protein food. Set against canned pineapple, another fruit entry in the database, a serving carries about 0.5 g less protein (canned pineapple has 1 g per 1 cup).