Molecular beam epitaxial GaAs/AlAs superlattices were grown on GaAs (311)A, (311)B, and (100) substrates at 600 degrees C. High resolution x-ray diffraction and transmission electron microscopy were employed to characterize the interface abruptness and the crystallinity of the superlattices. The high resolution x-ray diffraction results show a similar crystalline quality in both the (100) and (311) superlattices. A detailed analysis by transmission electron microscopy further reveals that superior interface profiles are achieved in the (311) superlattice. The observed inferior interface profile in the (100) orientation is most likely attributable to the meandering of steps during crystal growth.