Background: To compare the outcomes of debridement and total hip arthroplasty (THA) with antibiotic-loaded spacer implantation and subsequent THA for the treatment of patients affected by primary advanced septic arthritis (SA) of the hip in adults. Methods: All of the 20 patients (20 hips) underwent two-stage surgery. Nine patients were submitted to surgical debridement first, and then THA (group 1), while 11 patients were treated with antibiotic-loaded spacer and subsequent THA (group 2). Patients were evaluated based on the recurrence of infection, Harris hip score, visual analogue scale (VAS) pain score and leg-length discrepancy. Results: No cases of infection, deep vein thrombosis, death, and loosening of hip prosthesis were observed during follow-up. The mean follow-up time was 29.09 ± 10.80 months in group 1, and 28.22 ± 14.80 months in group 2. Before the THA surgery, the mean leg-length discrepancy was 2.80 ± 2.03 cm in group 1, and 0.50 ± 0.23 cm in group 2 (P < 0.05). In the latest follow-up, The Harris hip scores of patients was 90.33 ± 4.85 in group 1 and 94.36 ± 2.34 in group 2 (P < 0.05), respectively. There was no statistical significant difference in VAS pain score of the hip between the two groups (P > 0.05). Conclusions: Antibiotic-loaded spacer and subsequent THA is an effective method for the treatment of advanced SA of the hip in adults due to it can control infection and significantly improve functional hip.