The Middle Permian Qixia Formation and Maokou Formation sedimentary microfacies in Shizhu of Chongqing are the typical representatives in Sichuan Basin.Combined with the profile measurements in the field and the indoor microfacies analysis and according to the normal microfacies of Wilson,ten types of microfacies are recognized,that is green algal grainstone,marlite,fusulinid wackestone, bioclastic packstone, reef micrites, bioclastic-intraclastic packstone, dolomitization-silicification mud microcrystalline limestone,algal-mat (patellate)packstone,foraminifer packstone and bioclastic packstone.Combined with the analyses of the evolution sequences of lithological microfacies groups and the sedimentary facies,Qixia Formation and Maokou Formation are divided into the carbonate rock gentle slope and the carbonate rock platform.The carbonate rock gentle slope is again divided into the inner gentle slope and the outer gentle slope.The carbonate rock platform is again divided into the open platform,platform margin,foreplatform slope and some sedimentary microfacies .The sedimentary facies model is built and its evolution characteristics are discussed in this paper.The study provides important data for the regional geological research and the oil and gas exploration and development.%重庆石柱中二叠统栖霞组和茅口组是四川盆地的典型代表。以野外地质剖面宏观研究和室内显微镜下薄片分析相结合，参考 Wilson 的标准微相，识别出10种微相类型：绿藻颗粒灰岩、灰泥灰岩、蜓粒泥灰岩、生物碎屑颗粒灰岩、泥晶珊瑚灰岩、生物碎屑内碎屑泥粒灰岩、白云石化硅化泥-微晶灰岩、荷叶藻泥粒灰岩、有孔虫泥粒灰岩、生物碎屑泥粒灰岩。结合岩性微相组合的演化序列和沉积相分析，将栖霞组和茅口组划分为碳酸盐岩缓坡和碳酸盐岩台地两种沉积相，并将碳酸盐岩缓坡相划分为内缓坡和中缓坡两种亚相，碳酸盐岩台地相划分为开阔台地、台地边缘和台前斜坡3种亚相及其若干微相类型，建立了沉积相模式并讨论了其演化特征。
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