Electron paramagnetic resonance spectroscopy has been applied to obtain information on the in-plane anisotropy of Cu(II) [tetrakis-(3,3-dimethyl-1-butoxy carbonyl)] phthalocyanine (CuPcBC) molecules deposited as a Langmuir-Blodgett film on a biaxially oriented mylar substrate, We have found that the in-plane distribution of orientations of the film molecules depends on the angle between the asis of preferential order identified in the substrate and the dipping direction, The in-plane orientational anisotropy of the material in the film is mainly due to the ability of the substrate to induce oriented growth of CuPcBC molecules which reflects its surface order.