For more stable operation of radial AC hybrid magnetic bearing (radial AC HMB), it is particularly important to realize optimization design of parameters for its prototype. The paper focuses on solving the several typical defects of traditional methods and puts forward specific countermeasures on improving its disadvantages. Thus, a new parameter design method based on two sets of magnetic field system (the stator core magnetic field system and the air gap field system) is proposed to calculate the structure and electromagnetism parameters of the radial AC HMB. Using the proposed parameter design method, a finite element model of radial AC HMB based on the design results are simulated in finite element analysis software. The simulation results are consistent with the expected parameters calculation results very well, which show accuracy of the parameters and the proposed method. To illustrate the validity of the parameter design approaches further, the verification experiment is conducted. The operating experimental results show that the radial AC HMB has high stability, fast start of suspension and fine anti-disturbance. Moreover, system performance comparison results show the control system based on the new parameter design method has stronger anti-disturbance characteristics than that based on the traditional parameter design method.