Beam Gleam is a vertical scrolling shoot 'em up played on a vertical screen. The ship cannot shoot, but is able to destroy its enemies by reflecting their lasers using a directional mirror.
The player can rotate his ship's mirror in order to reflect the lasers fired at him. The ship's position is essential to correctly aiming the reflected laser, as it can affect its angle. It also features a shield with limited use, which can be obtained by picking up items.
Combos are achieved by destroying multiple enemies at once. Extra points can be scored by killing the enemy that fired the laser. The scoring system also requires to collect shield items which, when fully charged, will increase the player's rank.
Designed to be played on an arcade machine, Beam Gleam is presented as such, with an Attract mode and a credit management system ("Insert coin").