The carbonate rocks of the Cambrian in Yichang area are well developed. Limestone is mainly distributed in the Tianheban Formation and Shuijingtuo Formation of the lower Cambrian, as well as the Shipai Formation of the lower Cambrian and Keqibao Formation and Guanshannao Formation of the middle Cambrian. It can be divided into grain limestone (oolitic limestone, oncolitic limestone, calcirudite and calcarenite), grain-bearing micritic limestone (bioclast-bearing micritic limestone) and micritic limestone. Dolostone is the main rock type of this area. According to the mechanism of dolomitization, it can be divided into penecontemporaneous dolostone and post-penecontemporaneous dolostone.  Micritic dolostone distributes widely in the middle and upper Cambrian and is yellowish brown and brick-colored red, in which parallel laminae, bird’s-eyes and mud-cracks are developed. According to whether remnant grains exist, post-penecontemporaneous dolostone can be divided into remnant grain dolostone and crystalline dolostone. Crystalline dolostone is formed by seepage-reflux dolomitization and burial dolomitization.    According to petrology, biological assemblage and structural features of carbonate rocks, the auther reconstructed the sedimentary environments of formations of the carbonates in Yichang area.