The photoacoustic(PA) technique has been testified to be versatile and also reliable for measuring the thermal properties of most materials. For example, it has been utilized to verify the thermal diffusivity of semiconductors, polymers, superconductors, metal, and glass. In this study, the thermal diffusivity of the sago starch and chitosan polymer blend films was characterized using the laser-induced photoacoustic technique. It is based upon the theoretical analysis of the measured photoacoustic signal as a function of light modulation frequency. The value of thermal diffusivity is found to be dependent on the blend composition and further validation was performed through FTIR analysis. The optical transmission spectra show that the blend films process good optical transparency and improved surface quality when compared to the pure sago starch film.