Objective To introduce a new method of circumcision combined with Z-plasty and its effect in treating phimosis by keeping the Buck’s and Colle’s fascia from removal.Methods After 1% lidocaine was injected superficially to the tunica albuginea around the penile root,the excess skin at both the inner and external lamina of the foreskin was removed while dartos was kept intact,except in case of a circumferential contracture,some longitudinal incision was made within the dartos to release the contracture.A Z-plasty was also used to prevent the circumferential contraction when suturing.Results Twenty cases of phimosis were treated by this method with a satisfactory result including less hemorrhage during operation,less swelling postoperatively and less complications.Conclusion The detachable sleeve circumcision with Z-plasty has the following superiorities in treating phimosis: less operative injury,less swelling after operation,no adhesion of the foreskin to the tunica albuginea,neither the contracture of the incisional scar.