The paper presents the effect of blend composition on the pyroelectric behaviour of solution grown cellulose acetate-polyvinyl acetate (CA-PVAc) polymer blends under different polarizing fields and temperatures. For pure CA films the pyroelectric coefficient exhibited anomalous behaviour starting from a negative value at low temperatures, changing sign at intermediate temperatures and then rising montonically at higher temperatures. In contrast, pure PVAc films showed normal behaviour, with a positive value throughout the temperature range studied. The pyroelectric behaviour of blends showed a systematic variation with the ratio of individual constituents. As the concentration of PVAc in the blend was increased from 20% to 80% by weight, the pyroelectric behaviour varied from that of pure CA to that of pure PAVc, showing good mixing of the individual polymers in the blend. The origin of pyroelectricity in these blends is explained in terms of existing theories.