Abstract: The sub-acute toxicity study of malic acid-propane 1,2-diol copolyester (MPC) was carried out in rats. The polymer was administered intraperitoneally to the rats at a dose of 300 F g rat G 1 day G 1 for 21 consecutive days. The gross general observations such as changes of body weight, hematological profiles, biochemical parameters of blood and the histopathology of liver, kidney, heart, lungs and spleen were investigated both in control and experimental rats. The body weights of the rats were slightly increased. The changes of hematological and biochemical parameters were statistically insignificant. No abnormalities were found in the histopathology of the liver, kidney, heart, lung and spleen in the experimental group of rats when compared with control group of rats. From this study, it was inferred that malic acid propane 1,2-diol copolyester would be used as an enteric coating material.