Machining error of vibration beam rate sensor and its influencing to the performance of solid vibration inertial sensor were studied. The dynamics model was analyzed, and the mechanism error caused by the technology limit was studied and the theory of deducing the error was presented. Numerical calculations combined with 100mm alloyed vibration beam have been made. Results showed that quadrature error is the primary factor of affecting gyro’s performance; the error caused by mass center deviation of vibration beam change with angular acceleration, which can be ignored under the condition that small angular acceleration. The affects of parasitic Coriolis error on performance is minimal, which can be neglected. Finally, the quadrature error’s simulation results were consistent with expected results. The result also proved that restraining and compensating quadrature errors is one of the key technology to increase the performance.