Abstract: This study was aimed to evaluate the effect of backfat loss on reproductive performance of sows from the first parity to the second parity. The backfat loss were determined and reproductive performance differences were analyzed. The results showed that the total litter size of sows decreased significantly when the loss of backfat was more than 2 mm from the first parity to the second parity. Linear regression analysis showed that the backfat of first parity parturition sows should not exceed 18 mm.