Abstract: The Cunninghamia lanceolata forest(S), Ph. edulis -C. lanceolata mixed forest formed by the expansion of Ph. edulis into C. lanceolata forest(H) and Ph. edulis forest formed by the long-term expansion of Ph. edulis(M) were targeted in Fengyang Mountain, Zhejiang Province. High-throughput sequencing was used to measure the composition of the bacterial community, and the relationship between soil bacterial community diversity and soil physical and chemical properties in three forests were analyzed. The results showed that, the Operational Taxonomic Units(OTUs) and diversity index of soil bacterial communities were not different between the C. lanceolata forest and Ph. edulis-C. lanceolata mixed forest, but the OTUs and diversity index of soil bacterial communities in Ph. edulis forest were significantly higher than those in other forests. The numbers of unique OTUs were 759, accounting for 24.8% of the total OTUs of soil bacteria in Ph. edulis forest. The abundance of soil bacterial groups in bamboo forest changed greatly. The abundance of acidothermus, norank_f__norank_o__Elsterales, norank_f__Xanthobacteraceae and HSB_OF53-F07 genera decreased significantly, and a large number of new groups with abundance less than 1% appeared. The soil pH value and available phosphorus content of Ph. edulis forest increased significantly. Redundancy analysis showed that the diversity index of soil bacterial communities was positively correlated with soil pH and available phosphorus, negatively correlated with soil bulk density, but weakly correlated with soil organic carbon. The research shows that the expansion of Ph. edulis into C. lanceolata forest is beneficial to the improvement of soil quality and soil biodiversity, which provides a reference for the evaluation of ecological function and ecological control under long-term expansion of Ph. edulis forest.