LiNbO3 films, which were based on a non-hydrolytic sol-gel route, were deposited on LiTaO3 (0 1 2) and MgO (0 0 1) substrates. After drying, thin films with amorphous structure were obtained. During heat treatment followed by drying, amorphous structure changed into crystalline structure. Both cases of LiNbO3 films showed high orientation of LiNbO3 (0 0 6) planes as well as other orientations. The influences of substrate structure were investigated through the lattice matching mechanisms. A lattice matching relationship could be proposed as LiNbO3 (0 0 6)[2 1 0]//MgO (0 0 1)[1 1 0] for LiNbO3/ MgO system, and an indirect matching relationship of LiNbO3 (0 0 6)[-1 1 0]//LiTaO3 (0 1 2)[1 0 0] for LiNbO3/LiTaO3 system.