Abstract: This experiment is designed to explore the impact of wet fermented soybean meal on performance, eggs quality, serum antioxidant function, fecal composition of laying hens, which will provide scientific basis for the wet fermented soybean meal feed in laying hens. A total of 1152 375-day-old hens were randomly divided into 4 groups, each group was set up 6 replicates of 48 laying hens for a 90 days feeding trial. TreatmentⅠas control group was fed with the basal diet. TreatmentⅡ,Ⅲ,Ⅳwere fed with the basal diet in which part of soybean meal was replaced with 4.5%, 6.0% and 7.5% of the wet fermented soybean meal. The results showed as follows：the average egg weight of groupⅡand groupⅣsignificantly increased (P＜0.05). The broken eggs rate of groupⅢsignificantly decreased (P＜0.05). There was no difference among the average rate, feed- gain ratio and death and culling rate (P＞0.05). The eggshell thickness of groupⅣ, the yolk colorimetric values of groupⅢand groupⅣsignificantly increased (P＜0.05 or P＜0.01). The shape index odds ratio of groupⅢsignificantly decreased (P＜0.05). The serum catalase (CAT) activity of groupⅡ significantly increased (P＜0.05) and the malondialdehyde (MDA) content in serum decreased (P＜0.05). The total antioxidant capacity (T-AOC) of groupⅢsignificantly increased (P＜0.05). The amount of fecal crude ash of groupⅢsignificantly decreased (P＜0.01). The phosphorus content of groupⅣwas significantly lower (P＜0.05). It is concluded that using moderate wet fermentation soybean meal to replace ordinary meal in laying hens feed can improve the egg weight and egg quality, reduce emissions of fecal nitrogen and phosphorus. The suitable alternative amount is 6.0% to 7.5%.