By analyzing the light intensity of the ring laser gyro (RLG) and its performance changes with variations of the environmental temperature, a new method is put forward. The angle controllers of a novel cavity length and angle control mirror-light path and optical path length control mirror are used to realize the closed\|loop control of the ring laser of RLG in a similar way to the dither frequency stabilization (hill climbing). The modulation signal conflict is settled by controlling all the functional units in time-sharing control means. The optical path length and the light path of the ring laser are stabilized when the environmental temperature changes. The experimental results show that in the whole range of -40 ℃~+60 ℃, in the condition that the original intensity fluctuation reaches 30% or the intensity is very feeble, the light intensity variation is modulated within ±3% with the controlling system, and even stabilized light intensity level is kept when the original intensity is zero under extremely high and low temperatures. The system resolves the environmental temperature influences on the RLG.