AIM:To search for an excellent therapy for patients with concomitant exotropia.METHODS:In 120 patients patients with concomitant exotropia,60 patients underwent the strabismus operation in master eye,and the other 60 patients underwent strabismus operation in slave eye.The changes of visual acuity,surgical amount and stereopsis vision of the patients after operation were recorded.RESULTS:Compared with slave eye operation,the surgical results were better in the master eye operation in surgical amount (P<0.01),post-operation visual acuity(P<0.05) and stereopsis vision(P<0.05).CONCLUSION:Master eye operation on patients with concomitant exotropia have better effect than slave eye operation.