Sonic 3D Blast, known as Sonic 3D: Flickies' Island (ソニック３Ｄ フリッキーアイランド, Sonikku Surīdī Furikkī Airando?) in Japan and Europe, is an isometric platform game and the second 3D game in the Sonic the Hedgehog series, after Sonic the Fighters. It was developed in the United Kingdom by Traveller's Tales and published by Sega. Primarily developed as the last Sonic game for the Sega Genesis, it was later ported to the Sega Saturn and Microsoft Windows, and later re-released on many compilations and digital distribution platforms as well.

A separate game, titled Sonic Blast, was also released for the Sega Game Gear in the same year. However, much like the Game Gear versions of Sonic the Hedgehog and Sonic the Hedgehog 2, they are similarly titled but decidedly different games.