Ocean wave energy has a higher energy density than other renewable resources such as solar, wind, and tide energy. In recent years, a various ocean wave energy extraction systems have been proposed and established. But the average speed of ocean wave is generally slow. This will lead the traditional linear generator with disadvantages of large weight and low power density. In order to solve this problem, there are a lot types of magnetic gear have been applied to increase the speed of the motor. But some of them are complex to manufacture and may cost a lot. Furthermore, the complex structure will reduce the stability of the generator device and make it unsuited for long-term operation in the sea. The FM-TLPMG with quasi-Halbach magnetization proposed in this paper is similar to the traditional cylindrical linear motor in the structure. Its simple structure and higher power density make it suitable for direct ocean wave conversion. But they operate in a completely different principle. The FM-TLPMG combined with the magnetic field modulated technique can accelerate the speed of the traveling magnetic field by the teeth in the primary. So the magnetic field distribution is a crucial step in the analysis and design process of this motor. The analytical solutions of magnet and armature magnetic field distribution of the proposed motor have been validated by finite-element calculations. Comparing analytically predicted and FEA calculated field components distributions for a given position that can be seen that the analytical prediction agrees well with FEA results.