The edible parts of them are different. The main edible part of lettuce is the stem. The main edible part of lettuce is leaves. Their shapes are different. Lettuce leaves are wider and lettuce leaves are smaller. The two are specifically introduced as follows:

1, lettuce, lettuce species of Compositae can form a variety of tender stems, biennial herbs. Alias lettuce, lettuce, green shoots, lettuce. The above-ground stems are edible, the skin is white and green, the meat is crisp and tender, the young stems are green, and they turn white and green after maturity. Mainly edible tender stems, which can be eaten raw, cold, fried, dried or pickled.

2. Lettuce is an annual or biennial herb in Compositae. The stem is erect, solitary, the basal leaves and lower stems and leaves are large and undivided, oblanceolate, oval or oval, and the main edible part is leaves.