Frog Mario is an alternate form of Mario and Luigi that can be attained by acquiring a Frog Suit in the game Super Mario Bros. 3. Frog Mario can swim faster than regular Mario, allowing him to overcome currents in his path. Controlling Mario while swimming is also easier, as he can stop instantly, in a single spot in the water, and swim in any direction. However, Mario's on-land mobility is greatly decreased, and he cannot crouch or Slope Slide. In fact, he can only hop on the ground like a frog (Though he can walk and run while carrying an item, such as a Koopa Shell.). As such, Frog Mario's jumping ability is greater than regular Mario's. The Frog Suit will also prevent the player from slipping on Ice Blocks.
A form of Frog Mario appears in Paper Mario: Sticker Star when a Frog Suit sticker is used; it only overlays the sticker onto Mario, rather than turning him into Frog Mario. With this sticker, Mario can dodge enemy attacks by jumping, and his jump attacks are also stronger.
Frog Mario also appears as one of the unlockable Mystery Mushroom costumes in Super Mario Maker. Also, in that game, Super Mario Maker for Nintendo 3DS, and Super Mario Maker 2, Weird Mario may appear in this form if a Warp Door is knocked in Edit Mode in the Super Mario Bros. 3 style.
Frog Mario appears in Paper Mario: Color Splash, via use of a Frog Suit card. It works like it did in Paper Mario: Sticker Star, letting Mario jump over enemy attacks. It only lasts until Mario takes damage (this physically removes the Frog Suit, as in Super Mario Bros. 3) or wins the fight.