Abstract:The intestinal mucosal microbiota plays an important role in regulating the physiological functions of the host, and its structure and composition are modulated by multiple factors. The host sex is regarded as a key factor shaping the gut microbiota. However, the effects of different sexes on intestinal mucosal microbiota remain unclear. [Objective] To investigate the differences of the composition and functions of the intestinal mucosal microbiota between male and female Jiangshan Black pigs. [Methods] This study analyzed the ileal and colonic mucosal microbiota of eight sexually mature female and eight male Jiangshan Black pigs by 16S rRNA gene high-throughput sequencing. [Results] The Chao1 index and Shannon index of the ileal mucosal microbiota in male pigs were higher than that in female pigs (P<0.05). However, the two indexes of the colonic mucosal microbiota had no significant differences between the male and female pigs (P>0.05). The ileal mucosa of female pigs had higher relative abundance of Serratia and Escherichia_Shigella and lower relative abundance of Oscillospiraceae UCG-005, Alloprevotella, Blautia and Prevotellaceae_NK3B31_group than that of male pigs (P<0.05). The colonic mucosa of female pigs had higher relative abundance of unclassified_Muribaculaceae, Rikenellaceae_RC9_gut_group, and Prevotellaceae UCG-003 and lower relative abundance of Oscillospiraceae UCG-005, Lachnospiraceae_NK4A136_group, and unclassified_Lachnospiraceae than that of male pigs (P<0.05). Functional prediction results showed that the intestinal mucosal microbiota of male Jiangshan Black pigs was mainly enriched with functional pathways such as amino acid metabolism, carbohydrate metabolism, and energy metabolism (P<0.05), while the colonic mucosal microbiota was mainly enriched with functional pathways such as ABC transporters and two-component signal transduction systems (P<0.05). [Conclusion] The structure and function of intestinal mucosal microbiota were different between male and female Jiangshan Black pigs. The results provide references for understanding and excavating the intestinal microbial resources of local breeds of domesticated animals in China.