The invention relates to a birefringent compensating resonant cavity with double bars connected in series, belonging to the laser technology. According to the existing compensating technology, a rotator is arranged between two laser bars and the birefringent effect generated by one laser bar is compensated by the other laser bar, thereby the compensating effect is unsatisfactory. The birefringent compensating resonant cavity with double wave plates consists of two semiconductor side pumping modules internally provided with the laser bars, one concave surface output mirror, one concave surface fully reflected mirror and two quarter wave plates. The main surfaces of the laser bars in the two modules are overlapped with the focal points of the output mirror and the fully reflected mirror, respectively. One quarter wave plate is arranged between the output mirror and the pumping module and the other wave plate is arranged between the fully reflected mirror and the pumping module. The laser passes through the laser bar and the wave plate, and then repeats this process after being reflected by a cavity mirror, in addition, the birefringent effect generated by the laser bar is compensated by itself in the process. Both laser bars respectively compensate the birefringent effects generated respectively. The birefringent compensating resonant cavity has a simple structure and favorable compensating effects, and can obtain laser output easily with high power and high beam quality.