With the rapid development of wind power industry and the increasing tension of land resources, WTGS(Wind turbine generating set) changes from Onshore wind machine to offshore wind machine. Because the offshore wind turbine works in the complex environment, it is a higher challenge for tower security. This paper focuses on the load analysis of 2.5MW wind turbine tower, in which a segment solution is applied. Wind load is solved in the superior segment of tower. In the lower segment, the coupling factor of wind and wave is taken into account. Irregular waves are simulated on the basis of the linear wave theory, and then wave load is derived. Accordingly, loads on the tower are calculated by using MATLAB software, and the load spectrum of every node is drawn, which lays a foundation for the dynamic response analysis and fatigue life analysis of tower.