對比了GB/T 50344—2019等3個標準中里氏硬度換算建筑結構鋼材抗拉強度結果的差異，結合理論分析和試驗研究對形成差異的原因進行了探討，并對建筑結構鋼材硬度與強度的換算關系進行了研究。通過回歸分析給出了里氏硬度換算強度的換算公式及相對偏差，并與標準中的換算值進行比較。結果表明：3個標準中里氏硬度換算建筑結構鋼材抗拉強度結果差異較大是因為試樣的加工和固定方式不同；工程現場檢測時，如果不進行適當的支承或耦合，同一塊鋼板不同位置的檢測結果會有明顯的差異，鋼板越薄，差異越大。采用耦合的方法進行里氏硬度檢測時，鋼板里氏硬度和強度之間呈正相關，換算值相對偏差基本能夠滿足現場工程檢測的要求，可應用于工程實踐。

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.