To address the bulk and inflexibility of traditional analog dither system, a new digital dither control method for ring laser gyroscope (RLG) was designed by using single chip processor. The dither mathematical model was built and dither characteristics were investigated for square/sine wave driving signals respectively. By comparing the driving effect, it is found that the square wave driving has different variation rate of dither magnitude and nonlinear random noise infusion method. Simulations and experiments illustrate that the new method can control the RLG dither well and assure the performance.