The game was originally intended to be the fifth installment of the Super Mario Bros. series, with two leaked prototypes from December 1994 featuring a title screen with the logo Super Mario Bros. 5: Yoshi's Island. Come the final release, and the prefix would be shortened to Super Mario. This explains why the international release was titled Super Mario World 2: Yoshi's Island, as the original Super Mario World was subtitled Super Mario Bros. 4 in Japan.

Additionally, the later of the two prototypes features a radically different design for the logo, using a much sleeker and blockier font. The final release would revert to the earlier logo, barring the aforementioned truncated prefix.