Space Invaders '91, known as Space Invaders '90 in Japan and simply title Space Invaders in Brazil, is a Space Invaders title released exclusively for the Sega Mega Drive/Genesis in 1990/1991. It was never released in Europe.

Space Invaders '91 keeps the formula seen in the original game mostly intact, however instead of having four static shields it gives the player's ship extra hit points. The graphics have been improved and music has been added. Later levels in the game also introduce new enemies with different movement patterns.