Abstract:To investigate the level of follicular development and the expression of hormone secretion regulatory genes in shan partridge duck at different stages, the morphological changes of follicular wall of different developmental grades were observed, and the expression of CYP19 A1 and 3 beta-HSD was detected. It was found that the number of granular and membranous cells increased during development, density and thickness also increased with cell proliferation. According to the results of the expression of CYP19 A1 and 3 beta-HSD in the follicular membrane and granular layer of laying ducks, CYP19 A1 gene in the granular layer of follicles were mainly expressed at the pre-grade stage, 3 beta-HSD genes were mainly expressed at the grade stage, while CYP19 A1 and 3 beta-HSD genes in the follicular layer were mainly expressed at the grade stage.