Objective:To establish a fibrin zymography method for identifying the active proteins in lumbrokinase,and investigate the production difference and batch consistency of 5 different manufacturers. Methods:Fibrin zymography was used with the final con-centration of fibrinogen of 5 × 10 - 4 g·ml - 1 ,renature time of 30 min in 2. 5% Triton-x-100,incubation time of 30 min in PBS buffer (pH = 7. 4)at 37℃ and the protein concentration in the sample of 5. 0-37. 5 μg. Results:The sensitivity of the method was high,and the molecular weight distribution of active protein bands for the samples from five manufacturers was between 15KD and 40KD with 6 common active protein bands. The zymography of the samples from the five manufacturers had slight difference,while various batches of the samples from the same manufacturer showed no difference. Conclusion:The method is special. It can reflect molecular weight distribution and species of active protein,batch consistency and production process stability. It is easy to be standardized and suitable for the identification of lumbrokinase,which can lay foundation for the quality consistency evaluation of marketed products.