Gas-liquid two-phase flow is prevalent in various fields such as chemical engineering, petroleum and natural gas transportation, and the nuclear industry. As a crucial parameter of gas-liquid two-phase flows, pressure drop is essential for the accurate measurement and precise prediction of two-phase flow rates. In this paper, a pressure drop measurement system is designed, and experiments are carried out under the pressure range of 0. 1 ~ 0. 5 MPa. Pressure drop is measured for horizontal gas-liquid two-phase flow in the pipe with an inner diameter of 50 mm at different pressures. The influence of experimental characteristic parameters on pressure drop is analyzed and discussed. A pressure drop experimental database is established and existing pressure drop prediction correlations are compared and verified. The results indicate that the existing pressure drop correlations are not applicable to high pressures and large-diameter pipes. Therefore, a new pressure drop correlation is proposed based on the analysis of the experimental parameters. When compared with the experimental database, over 93% of experimental data exhibit a relative error within ±30% , and the mean absolute percentage error is 13. 57% . This verifies the extrapolative capability and applicability of the new pressure drop prediction correlation.