Objective:To estimate the precision and accuracy performance of blood gas analyzer(MB-3100) for three measuring indicators: pH, pCO2 and pO2.Methods: The evaluation of precision was achieved by testing quality controls of BIO-RAD, and the mean, SD and CV of the results were calculated according to protocol EP5 of Clinical and LaboratoryStandards Institute(CLSI). The evaluation of accuracy was achieved by comparing MB-3100 and Rapidlab 1265 according to the EP9-A2 of CLSI, and the consistency check of the two detection systems were analyzed by using paired t- test and equation of linear regression. All of these results were analyzed by using SPSS19.0.Results: The results of the research showed that the precision performances of analyzer MB-3100 in various detection level were acceptable. And there was no statistically significant difference for the accuracy performances between the two systems on pH, pCO2 and pO2, respectively (t=0.042,t=1.489,t=-1.6,P>0.05). Moreover, both of the system errors of the two systems at different medical decision level were less than the corresponding total error allowances (TEa), respectively.Conclusion: Both of the precision and accuracy performances of MB-3100 blood gas analyzer are acceptable, and it can provide reliable reports for clinical practice.