A certain amount of bioherm are developed in the Lower Silurian Shiniulan Formation in southeastern Chongqing .Taking the Jiqiangtai outcrop in Wansheng of Chongqing and Houtan outcrop in Xishui of Guizhou as the main study targets ,we studied in detail the bioherm in the Lower Silurian Shiniulan Formation through field observation , ordinary thin section observation and carbon/oxygen isotope measurement .The bioherms mainly occur in the Upper and Middle Shiniulan in the study area and have a certain scale .Rock structure and carbon/oxygen isotopes reveal a change of sea level from slow rising to sharp declining .Depositional environment developed from shallow mixed continental shelf in the early stage to biological reef-shoal in the middle stage and finally to reef-front slope in the late stage .The aquatic environment was suitable for the coral bioherms and biological communities to thrive .The development of bioherm in the Lower Silurian Shiniulan in southeastern Chongqing was mainly affected by sea-level changes and terrigenous clastics in-put.Slow change of sea level was the basic condition for bioherm growth and the amount of terrigenous clastics input con -trolled the process of bioherm development .%渝东南地区下志留统石牛栏组发育一定规模的生物礁。以重庆万盛机枪台剖面和贵州习水吼滩剖面为主要对象，利用野外观察、普通薄片、碳/氧同位素等手段，对研究区下志留统石牛栏组生物礁进行了详细研究。结果表明，研究区生物礁主要发育石牛栏组中上部，且具有一定规模；岩石结构及碳/氧同位素变化揭示了该时期海平面由缓慢上升到急剧下降的变化过程，沉积环境表现为早期浅水混积陆棚-中期生物礁滩沉积-晚期礁前斜坡沉积的演化过程，水体环境适合珊瑚礁及生物群落的大量繁殖。由此证实了渝东南地区下志留统石牛栏组生物礁发育主要受海平面变化及陆源碎屑物质注入的影响，海平面的缓慢变化是生物礁发育的基本条件，陆源碎屑物质的多少制约了生物礁的发育过程。
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