To suppress spatial hole burning, a direction related polarizer is adopted in Er-doped fiber ring laser gyroscope. To decrease the frequency drift caused by fluctuation of environment temperature, the polarization maintaining (PM) fiber is substituted for single mode fiber in the ring cavity. To obtain better reciprocity, two 90-deg rotations of PM fiber are introduced. Through the manners, the stable single-mode continuous wave lasers are observed simultaneously in both output directions. At last, better performance of the ring laser gyroscope based on Er-doped fiber is achieved.