对金属材料室温拉伸试验的测量不确定度的来源进行了分析，通过建立数学模型和重复性试验评定了金属材料室温拉伸试验的测量不确定度。结果表明：作为规范化的检测试验室，在人员、机器、原料、方法、环境和管理等受控以及包含因子k=2的条件下，下屈服强度的相对扩展不确定度U_rel（R_eL）=2.9%，抗拉强度的相对扩展不确定度U_rel（R_m）=1.6%，断后伸长率的相对扩展不确定度U_rel（A）=2.8%，断面收缩率的相对扩展不确定度U_rel（Z）=2.1%；本文采用的评定方法可为金属材料室温拉伸试验测量不确定度的评定提供一定参考。

The source of the uncertainty of measurement in metallic materials at room temperature tensile test was analyzed, and the uncertainty of measurement of the metallic materials at the room temperature tensile test was evaluated by establishing mathematical model and repeatability test. The results show that as a standardized testing laboratory, under the controlled conditions of man, machine, material, method, environment and management, and under the condition of containing factor k=2, relative expansion uncertainty of lower yield strength U_rel (R_eL)=2.9%, relative expansion uncertainty of tensile strength U_rel(R_m)=1.6%, relative expansion uncertainty of elongation after fracture U_rel(A)=2.8%, relative expansion uncertainty of section shrinkage rate U_rel(Z)=2.1%. The evaluation method adopted in this paper provides reference for the evaluation of uncertainty in measurement of metallic materials at room temperature tensile test.