Abstract: Establishment of 24 sample plots of pure and mixed forest were carried out in September 2012 in Qiandaohu, Chun’an of Zhejiangprovince and determinations were conducted on DBH, tree height, etc. 13 factors of forest stand structure were selected including DBH, biodiversityindex, mingling to analyze relationship between these factors and carbon sequestration by principal component analysis. The coupling relationshipbetween forest structure and carbon sequestration was modeled. Comprehensive analysis by calculations of sample plots demonstrated that carbonsequestration of broad-leaved forest was better than that of mixed forest of conifer and broad-leaved, and that of confer forest was the last.