对比了GB/T 50344—2019等3个标准中里氏硬度换算建筑结构钢材抗拉强度结果的差异，结合理论分析和试验研究对形成差异的原因进行了探讨，并对建筑结构钢材硬度与强度的换算关系进行了研究。通过回归分析给出了里氏硬度换算强度的换算公式及相对偏差，并与标准中的换算值进行比较。结果表明：3个标准中里氏硬度换算建筑结构钢材抗拉强度结果差异较大是因为试样的加工和固定方式不同；工程现场检测时，如果不进行适当的支承或耦合，同一块钢板不同位置的检测结果会有明显的差异，钢板越薄，差异越大。采用耦合的方法进行里氏硬度检测时，钢板里氏硬度和强度之间呈正相关，换算值相对偏差基本能够满足现场工程检测的要求，可应用于工程实践。

The differences of results of Leeb hardness converted into tensile strength of building structure steel in three standards, such as GB/T 50344—2019, were compared, the reasons for the differences were discussed based on theoretical analysis and experimental research, and the conversion relationship between hardness and strength of steel for building steel structure was studied. Through regression analysis, the conversion formula and relative deviation of conversion of strength by Leeb hardness were given and compared with the standard conversion value. The results show that due to the different processing and fixation methods of samples, the results of conversion of building structure steel tensile strength by Leeb hardness in the three standards are quite different. In the engineering field test, if the appropriate support or coupling is not carried out, the test results of different positions of the same steel plate will have obvious differences, and the thinner the steel plate is, the greater the difference is. There is a positive correlation between the Leeb hardness and strength of steel plate when the coupling method is used for the test of the hardness of steel plate, and the relative deviation of conversion value can basically meet the requirements of field engineering testing, which can be applied to engineering practice.