The photoreactive amphiphile p-(stearylamido)benzoyl azide (SABAz) was synthesized and grafted onto surface of thin polyacrylonitrile (PAN) films by irradn. with UV light. Two different techniques were applied, namely, Langmuir-Blodgett (LB) deposition and casting from soln. A high degree of order and a hydrophobic surface were established by reflection-absorption FT-IR spectroscopy (RA-IR) and contact angle measurements. The stability against treatment with water, THF, and chloroform was tested. A considerable amt. of amphiphilic mols. remains on the surface also after treatment with chloroform. RA-IR spectra taken from photomodified PAN films prepd. by both techniques are almost identical after chloroform treatment, indicating a similar coupling mechanism.