Abstract: OBJECTIVE To optimize the enzymatic hydrolysis technology of anti-hepatic fibrosis active extractive from the degreasing ointment of Periplaneta americana by neutral protease. METHODS The hydrolysis degree, yield of active extractive and in vitro activity were used as evaluation indexes. On the basis of single factor investigation(enzyme dosage, enzymatic time, pH, enzymatic temperature, substrate concentration), the L₉(3⁴) orthogonal experiment was used to optimize the neutral protease hydrolysis of degreasing ointment of Periplaneta americana to prepare the active extractive of anti-hepatic fibrosis. RESULTS The optimum condition were as follows:enzyme dosage was 0.3%, enzymatic time was 2 h, pH was 8.5, enzymatic temperature was 45℃ and substrate density was 1.07. The results of process validation showed that the hydrolysis degree of Periplaneta americana degreasing ointment was 15.8%, and the yield of active extractive increased from 0.54% to 0.72%. The IC₅₀ values for 24, 48 and 72 h were (118.37±3.12), (115.16±2.48), (105.00±6.35)μg·mL^-1, respectively. CONCLUSION The enzymatic hydrolysis process of the active extractive of Periplaneta americana against hepatic fibrosis is optimized. The optimized process is simple and feasible, which laid a foundation for the follow-up study of the active fraction of Periplaneta americana.