Tsuyu is a short, slim girl who is frog-like in appearance. She has long, dark teal hair which she ties in a bow on her back. She has very wide eyes with pure black irises, and distinctive lower eyelashes. Like a frog, she has a wide mouth and a very long tongue.

Her Hero costume is a green and black skintight suit with yellow linings which imitate a frog's skin markings. She also wears goggles, gloves and boots with a frog-like design. Despite the fact that the boots are shaped like frog feet, she does have ten toes.