To compare pancreas and intestinal chyme lipase activities, crude fat digestibility between Arbor Acres (AA) broilers and Beijing fatty chickens at 21, 42 and 56 days of age, 96 birds for each broiler breed were randomly allotted to 3 groups with 4 replicates of 8 birds per replicate. Five birds from each replicate were killed and sample were taken at 1, 42 and 56 days of age. Lipase activities and crude fat digestibility were determined. The results showed that pancreas lipase activities of AA broilers achieved maximum at 42 days of age, and then from 42 to 56 days of age, gradually decreased. Lipase activities in intestinal chyme at 21 days of age were higher than those at 42 and 56 days of age（P＜0.01）. The crude fat digestibility changed following the same trend of pancreas lipase activity. Pancreas lipase activities of Beijing fatty chickens achieved maximum at 56 days of age. Lipase activities in intestinal chyme at 42 and 56 days of age were lower than those at 21 days of age. However, crude fat digestibility was not different at different days of age (P＞0.05). During this experiment, lipase activities in intestinal chyme of Beijing fatty chickens were higher than those of AA broilers at each day of age, but at 21 and 56 days of age were significantly higher (P＜0.05). Crude fat digestibility of Beijing fatty chickens was also higher than those of AA broilers, but only at 56 days of age was higher significantly (P＜0.05).