This study was conducted to determine the effects of emulsified fat powder on laying performance, egg quality, serum biochemical parameters and antioxidant activity. Four hundred 300-day-old Rohman laying hens were randomly divided into 4 dietary treatments of 100 each. Each treatment had 4 replicates, and each replicate had 5 cages with 5 hens per cage. The control group was fed with basal diet, and the experimental groups I, II and III were supplemented with 1%, 3% and 5% emulsified fat powder, respectively. The adjustment period lasted for 7d and the experimental period lasted for 30d．The results showed that dietary 3% fat powder supplementation increased the rate of egg laying and mean egg weight (P<0.05) and decreased the broken egg rate (P<0.05). Serum total protein, albumin and globulin concentration increased significantly in response to supplemental fat poeder and was also maximised at 3%. In addition, serum glucose and blood urea nitrogen (BUN) significantly decreased (P<0.05). The content of total cholesterol (TC) and total triglyceride (TG) of all experimental groups decreased compared with that of the control group, and 3% addition groups was the lowest (P<0.05). Compared with the control group, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the serum of all the trial groups were significantly increased (P<0.05), while the content of serum malondialdehyde (MDA) reduced. These results suggested the emulsified fat powder could improve the laying performance, enhance the egg quality and oxidation resistance.