Abstract: OBJECTIVE To analyze the prosthetic joint infection（PJI） and pathogens in patients undergoing artificial joint replacement, so as to provide evidence for early prevention and treatment of PJI.METHODS From Jan. 2013 to Dec. 2018, 3 128 patients undergoing artificial hip and knee replacement in a large center were selected as the subjects of study. Among them, 49 patients with revision surgery for treatment of arthroplasty infection were retrospectively studied.RESULTS Of the 3 128 patients undergoing artificial hip and knee replacement 49 had PJI. Periprosthetic infection occurred in 540（240, 1 260） days, for hip joint, early infection occurred in 17.50（10.50, 29.50） days and delay infection occurred in 360（255, 630） days and late infection occurred in 2 340（1 350, 4 050） days. The microbiological detection rate was 97.96%（48/49）. A total of 128 specimens were sent for examination, and 59 strains of pathogens were obtained. 48 strains of Gram-positive bacteria accounted for 81.36%（34 strains from hip joint and 14 strains from knee joint）, mainly Staphylococcus epidermidis and Staphylococcus aureus; 10 strains of Gram-negative bacteria accounted for 16.95%（7 strains from hip joint and 3 strains from knee joint）; and 1 strain of fungus accounted for 1.69%（from hip joint）.CONCLUSION At present, heterogeneity exists between the diagnostic criteria of PJI at home and abroad. The definitions of PJI clinical diagnostic criteria, CDC/NHSN nosocomial infection surveillance criteria（2016 edition） and nosocomial infection diagnostic criteria（2001 edition） are different. The proportion of cases with infection lasting more than one year after arthroplasty is 61.22%. According to the current domestic "Diagnostic Standards for Nosocomial Infection", a large number of PJI cases will not be monitored. Long-term follow-up and monitoring of patients undergoing arthroplasty is recommended.