【Abstract】 Objective To investigate the diagnostic value of albumin/fibrinogen ratio (AFR), C-reactive protein/(albumin/globulin) ratio (CAGR) and albumin (ALB) in the diagnosis of periprosthetic joint infection (PJI) after artificial joint arthroplasty. Methods The clinical data of 95 patients who underwent hip and knee revision at our hospital from January 2018 to January 2021 were retrospectively analyzed. Of these, 45 were diagnosed with PJI and 50 with aseptic loosening of the prosthesis (AL). The levels of CRP, ESR, fibrinogen (FIB), ALB, globulin (GLO), AFR and CAGR were statistically analyzed in the two groups. The sensitivity and specificity of each index were calculated using the subject operating characteristic (ROC) curve, and the diagnostic efficacy was compared based on the area under the curve (AUC). Results There was no statistically significant difference between the PJI and AL groups in terms of gender and age (P>0.05), but there was a difference in terms of surgical site (P<0.05). The area under the curve for FIB, ALB, AFR and CAGR were 0.869, 0.754, 0.864 and 0.825 respectively. The best cut-off values for the diagnosis of PJI were 3.955 g/L, 36.650 g/L, 9.070 and 13.960 for FIB, ALB, AFR and CAGR, with sensitivities of 82.0%, 86.0%, 92.0% and 90.0%, and specificities of 80.0%, 60.0%, 80.0%, and 66.7%, respectively. Conclusions AFR, FIB and CAGR can be used as new auxiliary indicators for the diagnosis of PJI.