Abstract: Based on scalar quantity magnet of tubular reference frame with separated variables, an analytic magnetic field calculation method was introduced, which is a way to work on the tubular permanent magnet linear synchronous motor with radial magnet. An elaborate academic analysis to magnetic field distribution of nonslotted motor was conducted, the result of which shows the axial and radial slot magnetic distributions. To the slotted motors, Carter coefficient was introduced and amendatory expressions of the analytic result were shown, meanwhile the thrust force of the motor was calculated analytically. Then, finite element analytic method was used to testify the calculation of the magnet and the force. It can be concluded that there is almost no difference between the error results of the above two methods. So it is accurate and practical to calculate the magnetic field using the method based on scalar quantity magnet of tubular reference frame with separated variables, as well as the thrust force.