The hard lumps under the foreskin after circumcision may be normal, or may be caused by improper suturing or infection. 1. Normal performance: in the circumcision surgery, due to the local damage, in the process of healing, it will lead to hard lumps under the foreskin, hard lumps are small, may gradually disappear, generally does not cause adverse effects. 2. Improper suture: after the operation may need to carry out suture processing, improper suture, there are hard lumps under the foreskin, and the size of the hard lumps is larger. 3. Infection: after circumcision, due to the existence of surgical incision, when the postoperative care is not appropriate, the surgical incision site is infected, the infection is more serious, and after the infected area is healed, it will make the subcircumcision hard pimples. After circumcision, there are hard lumps under the foreskin, hard lumps exist for a long time, and affect the quality of sexual life, it is recommended to consult a doctor for examination and treatment.