Derivatives of chitosan were synthesized by reacting chitosan with fatty acides. The contact angles on chitosan-stearate film were measured using dispersion(D), polar(P) and hydrogen(H) liquids. All nonpolar liquids of alkane homologues easily spread on the surface of chitosan-stearate film. On the other hand, polar or hydrogen-bonding liquids form a certain angle on the surface of chitosan-stearate film. The critical surface tensions γc of chitosan-stearate film were evaluated by the Zisman plot(cos θ versus γL) and the other plots. New functional film for MA packaging was developed to understand the relationship between surface chemistry and wettability of chitosan-stearate film.