Abstract：Objective：To explore the application value of Clinical and Laboratory Standards Institute (CLSI) guideline EP15-A3 for precision verification in clinical biochemistry. Methods：According to the design of EP15-A3 basic 5×5 precision experimental procedure, the results of 6 common biochemistry items including creatinine (Cr), urea, uric acid (UA), total cholesterol (TC), triglyceride (TG) and glucose (Glu) were verified for repeatability of intraassay and imprecision withinlaboratory by using the IFCC Rela (level 1) and Rela B (level 2) samples. The basic 5×5 design, i.e., one run per day for five days and five replicates per run, should yield 25 results for same sample. The outliers were calculated by Grubbs′ test, and one way ANOVA test was used to calculate the repeatability variance (S_R) of users and the withinlaboratory variance (S_WL). The manufacturer claims on imprecision, σ_R and σ_WL, were compared with the results respectively. S_R≤σ_R and S_WL≤σ_WL imply that the imprecision claims of manufacturer were verified by users. If S_R＞σ_R or S_WL＞σ_WL, the results should be further compared with the upper verification limit (UVL). S_R≤UVL_R and S_WL≤UVL_WL also imply that the imprecision claims of manufacturer were verified by users. Otherwise, the reasons of imprecision should be searched or the contact with the manufacturer should be needed. Results：The results of 6 biochemistry items were all passed through Grubbs′ outliers test, and there were no outliers. The repeatability SR and the withinlaboratory S_WL were compared with the manufacturer claims σ_R and σ_WL or calculated UVL_R and UVL_WL respectively, and showed that in the imprecision verification of intraassay repeatability experiments S_R≤σ_R was shown for each level of the 6 items, except for Cr (level 1), TC (level 2), GLU (level 2) which were S_R＞σ_R, S_R≤UVL_R. In withinlaboratory imprecision verification experiments, S_WL ≤σ_WL was shown for both level of the 6 items. 〖 Conclusion：The repeatability of intraassay and withinlaboratory imprecision of 6 Roche biochemistry items meet with the manufacturer claims and the requirements of quality objectives.