Abstract: The ontogenesis of digestive enzymes (proteases, α-amylases, lipases and phosphatases) in paddlefish Polyodon spathula was determined in larvae between 0-53 days after hatching (DAH). From initiation of exogenous feeding (3 DAH), larvae were fed Cladocera for 37 days in indoor cement pit, and then transferred to pond fed natural food. Fertilized eggs and larval fish samples day 3, 6, 12, 20, 30, 40, 44, 47 and 53 after hatching were taken as the test materials. The results showed that most of the digestive enzymes activities could be detected before the onset of the exogenous feeding. Alkaline protease activity was detected at 3 DAH and acid protease activity was quantifiable from eggs. Alkaline protease activity reached to the maximum level at 44 DAH (1.96±0.09) U/fish, followed by a decrease and then an increase on 47 DAH. The specific alkaline protease activity reached to the peak level at 53 DAH (8.84±0.59) U/mg protein. Acid protease had its maximum activity at 44 DAH (0.52±0.05) U/fish, its specific activity reached the first peak on 6 DAH (2.08±0.09) U/mg protein, followed by the minimum on 30 DAH (0.83±0.06) U/mg protein. Alkaline protease activity was consistently higher than acid protease activity. α-Amylases activity was relatively stable during incubation period in workshop (12 DAH-40 DAH) and reached to the maximum on 47 DAH (0.42±0.03) U/fish. Two peaks were found about the specific α-amylase activity, a small one on 12 DAH (1.18±0.12) U/mg protein and the maximum peak on 47 DAH (1.94±0.16) U/mg protein. Both lipase activity and specific lipase activity had one peak on 30 DAH (0.20±0.02) U/fish and 6 DAH (2.28±0.22) U/mg protein respectively. High lipase activity implied the importance of lipid utilization. The alkaline phosphatase activity and the specific phosphatase activity showed similar trends, with the exception of the maximum period, 44 DAH (0.08±0.00) U/fish and 30 DAH (1.96±0.15) U/mg protein respectively. Acid phosphatase activity had one peak on 3 DAH (0.01±0.00) U/fish, followed by a significant increase and reached maximum on 44 DAH (0.05±0.00) U/fish. Two main peaks were detected about the specific of acid phosphatase activity, one on 30 DAH (1.19±0.10) U/mg protein and the other on 44 DAH (1.10±0.08) U/mg protein. It suggested that protease, α-amylase and phosphatase activities increased with the ontogenesis of paddlefish, and alkaline protease was important to paddlefish larval. Acid protease, α-amylase, acid and alkaline phosphatase activities increased with growth decreasing and decreased with growth increasing when fish transferred to pond.