A high-resolution light-beam scanning apparatus utilizing only mass-producible holograms instead of utilizing auxiliary optical systems such as optical lenses or a mirror having curvature, and capable of compensating for disadvantages including scanning beam thickening and variation, failure of a rotatable hologram to rotate at a constant velocity, displacement of a scanning beam position in the scanning direction and the cross scanning direction due to a mode hop of a wavelength of a semiconductor laser, and deviation of a base of rotatable hologram from a parallel state. These disadvantages are detrimental to efforts for increasing the resolution of a hologram scanner and lowering the cost thereof. The light beam scanning apparatus includes at least two holograms, one rotatable and one fixed, wherein the fixed hologram plate has a phase distribution .PHI..sub.H represented as a difference obtained when subtracting a reference wave phase .PHI..sub.0 from an object wave phase .PHI..sub.R, where X is a scanning direction and Y is a cross scanning direction, C.sub.0, C.sub.1, C.sub.2, Y.sub.0, and Z.sub.0 are constants, where .lambda..sub.2 is a wavelength of said incident light; and .lambda..sub.1 is a wavelength of a constructing wave used for forming said fixed hologram plate.