In order to apply polyimide Langmuir Blodgett films to nematic liquid crystal (NLC) alignment, the optimum deposition conditions have been studied by measuring the azimuthal anchoring energy of 5CB aligned on the film. Special attention is paid to obtain good NLC alignment on the 2-type PI-LB flims, and we firstly prove that, by choosing the proper deposition conditions, the Z-type films show better performances of NLC alignment than Y-type films. The obtained azimuthal anchoring energy of the Z-type film exceeds 10−5J/m2, which is the strongest azimuthal anchoring energy of PI-LB films reported so far.