Abstract: Slaughter performance, sensory, and conventional physicochemical indexes of 300 days old Yanjin blackbone chicken and Piao chicken were measured and compared, to investigate the differences in slaughter performance and meat physicochemical properties between Yanjin blackbone chicken and Piao chicken. The results showed that both Yanjin blackbone chicken and Piao chicken had good meat performance, and the breast muscle rate of female Yanjin blackbone chicken was significantly higher than that of male Yanjin blackbone chicken and Piao chicken (P<0.05). The pre-slaughter weight, slaughter weight, eviscerated weight, breast muscle weight, leg muscle weight, and leg muscle rate of male chickens of the same breed were higher than those of female chickens (P<0.05), and the slaughter performance of male chickens was better. The appearance scores of the two chicken breeds were higher (6.30~7.30), and the leg meat had higher flavor, texture, taste, and overall acceptance scores than the breast meat. The pH values of the two breeds of chickens were within the range of high-quality chickens after slaughter, and the cooking loss rate, moisture content, crude ash, and crude fat of the leg meat of Piao chickens were significantly higher than those of Yanjin blackbone chicken(P<0.05). The cooking loss (P<0.05) and crude protein content (P<0.05) of leg meat were lower than those of breast meat in different parts of the same variety, while the content of moisture (P<0.05) and crude fat (P<0.05) was higher than that of breast meat. This study provided a scientific theoretical basis for the in-depth development and utilization of two excellent local chicken breeds and laid a foundation for establishing quality evaluation standards for Yunnan's high-quality local chicken.