To investigate the discharge parameters of the prism laser gyro under high-frequency excitation, a finite element simulation model is developed using a prism gyro structure with an optical length of 0.28 m. The optimal high-frequency excitation parameters were determined by simulating the effects of high-frequency discharge, voltage, size of the electrode plates, and horizontal displacement of the electrode plates on the gas discharge: high-frequency voltage is 6.5 to 7.5 V, frequency is 130±5 MHz, flat electrode discharge structure is used, and upper and lower electrode plates are 16×5×2 mm3 and 12×5×2 mm3, respectively. It is preferable that the center positions of both upper and lower plates be as symmetrical as possible. Finally, the experimental results validate the accuracy of the finite element analysis.