A study was conducted out at Experimental animal farm in Binh thuy district, Cantho city to determine the optimal supplementation of  Psophocarpus scandens in diets on reproductive performance of Crossbred  rabbits. A total of 30 rabbits at 5-6 months of age were arranged in a completely randomized design with 5 treatments as 5 diets and 3 replicates, with 2 animals per experimental unit and the trial was done in 3 litters. The treatments were 5 different Psophocarpus scandens supplement levels from 9, 18, 27, 36 and 45g (DM), corresponding to CĐ9, CĐ18, CĐ27, CĐ36 and CĐ45, respectively. In 3 litters the results show that the daily CP intake significantly increased (PPsophocarpus scandens levels in the diets, while NDF intake decreased (PPsophocarpus scandens had higher reproductive  performances. There was increase of milk productivity, and litter sizes at birth and at weaning  in litter 2 and 3 as compared those in litter 1.