Abstract:Objective：To discuss the influence of different modes of sample processing on blood alanine aminotransferase（ALT）testing. Methods：The blood samples were collected from 160 healthy blood donors and the ALT level of the samples were tested by rate method. In this study，we optimized different processing conditions to the detection of ALT，such as the sequence of centrifugation and storage，separation with anti- and pro-coagulant tubes，different storage times and centrifuge temperatures. The results were analyzed by t-test，and P < 0.05 was considered as significant difference. Results：There were no significant differences of ALT levels in samples using different order of centrifugation and storage or different blood-collecting tubes，respectively（p > 0.05）. The ALT levels were significantly changed when samples were stored for 8 hours before test compared to 0 and/or 4 hours storage. The same results occurred in different centrifuge temperature（p < 0.05）. Conclusion：It is indicated that after sample collection，storage times and centrifugation temperature influenced the result of ALT test to some extent. As the important part in the quality control of ALT detection，storage time and centrifugation temperature should be attached enough importance. If cannot be analyzed immediately，samples should be stored at 2-8 ℃ for some time，and should be centrifuged within 4 hours for serum collection. Serum and plasma can be used as a substitute for daily work if necessary.