Unicompartmental knee arthroplasty (UKA) is an effective means of treating severe knee monomesooeciumarthritis. By preserving normal cruciate ligaments and patella of the knee, UKA limits the volume of bone cutting, retaining normal kinematics and mobility of knee joint at a relatively high level. Compared to total knee arthroplasty (TKA), UKA has its advantages of low expense, less trauma, rapid recovery and good function. Infection after joint replacement is a disastrous complication with an incidence rate of 0. 5%?3%, often resulting in failure of operation and great physical, psychological and financial burden to the patient. Revision operation (thorough debridement + removal of the prosthesis + antibiotic bone-cement implanting + local or systematical application of antibiotics + joint replacement) is the golden rule of treating joint infection. The orthopaedics department of the third affiliated hospital of Southern Medical University performed 75 UKA from January 2014 to January 2016, with only one infection case. Through symptomatic treatment and nursing care, the infection is under control and the patient is discharged from the hospital, with no recurrent infection found in follow-up visits so far. Following is the clinical case report.