A simple screening technique of hydrogen embrittlement (HE) of steels for hydrogen energy facilities using an in-situ small-punch (SP) test method under external hydrogen condition has been established. Using this method, we investigated the HE behaviors of API X70 steel welds under test conditions mimicking pipeline operating environments. The HE sensitivity at each region of the base metal, heat-affected zone, and weld metal of the steel weld was examined qualitatively and quantitatively and compared to one another. Under 8 MPa H2 gas, the welds showed pronounced HE: the HE behaviors induced were similar across all tested regions. This shows that the in-situ SP test is effective for screening HE susceptibility of pipeline steel welds in high-pressure hydrogen environments.