Abstract: In order to discover the function and mechanism that Perilipin (PLIN) gene acted on fatness traits of chicken，we adopted the real-time PCR method to test the relative expression quantity of PLIN gene in breast muscle，liver， abdominal fat and subcutaneous fat of Sichuan Mountainous Blackbone chicken at 7 growth points， including 1，14，28，42，56，70 and 84 day.We also tested each bird′s comb weight， living weight， subcutaneous fat thickness and intramuscular fat content in breast muscle. The results showed that the order of the relative expression quantity of PLIN gene in four tissues from high to low was abdominal fat， subcutaneous fat， breast muscle， and liver for all the growth points， except for 28 and 70 day. And the relative expression quantity of PLIN gene in abdominal fat and subcutaneous fat were increasing along with the growth of bird. Furthermore， the developmental variations of relative expression quantity of PLIN gene in abdominal fat were positively related with those of subcutaneous fat thickness（P≤0.01）. And the developmental variations of relative expression quantity of PLIN gene in breast muscle were positively related with those of intramuscular fat content （P≤0.01）. We inferred PLIN gene was a key regulator of the fatness traits development in chicken.