The radial sandbar is an important planning area of offshore wind power in Jiangsu province. It is of great significance to study the horizontal bearing characteristics of large diameter monopile in this area for offshore wind power engineering. Based on the research method combining the field test and finite element numerical simulation, the numerical analysis of the horizontal ultimate bearing capacity of the monopile is carried out. The main conclusions are as follows :(1) the deflection along the test pile tends to be zero near the pile toe, characterized as the flexible pile. With the increase of the horizontal load, the maximum bending moment of the test pile increases gradually, and its position gradually moves down, which is about 2.2D～2.5D below the soil surface; (2) the prediction model of the horizontal ultimate bearing capacity of the large diameter monopile is proposed. The predicted values of the horizontal ultimate bearing capacity of the monopiles based on the model are in good agreement with the numerical simulation results. The average relative error is only 4.9%, and the maximum relative error is less than 11%.