Alien Invasion is a fixed screen shoot 'em up based on Space Invaders but with some additions to the gameplay. There are twelve different invaders in the game including one that takes two hits to kill. The invaders have three different kinds of bomb: normal bombs that drop straight down, spinning bombs that drop diagonally and homing bombs that seek out the player. A notable difference from Space Invaders is that the old shields are gone. Instead the laser base has a built in shield that can be activated for protection. The player starts out with two shields and get new ones at the start of each new wave. The UFOs acts as supply ships and will randomly drop power ups that the player can catch. Power ups include extra lives and shields, stopping the invaders from moving or dropping bombs and movable rockets. There's also a power up that makes the invaders invisible.

The game also comes with editors that allow the player to change sprites and wave formations.

Originally published by Alien Visions in 1990, it was re-released in 1994 by Archimedes World.