OBJECTIVES: To evaluate the profile of patients undergoing hip replacement (THR) or knee replacement (TKR) surgery and the associated costs with surgery according to public health care system (SUS) perspective. METHODS: A review of a government administrative claims database (DATASUS) was conducted for patients who underwent a THR or TKR procedure between January 2009 to March 2011. Data regarding gender, age and mean costs per patients were analyzed for the entire period and data for procedures costs were collected per year, as some of them were excluded from SUS procedure list. RESULTS: A total of 41,862 patients were identified at study period (12,476 for TKR and 29,386 THR).  Average age was 65,6 (SD 10,5) for TKR and 64,1(SD 14,9) for THR, being women more frequently submitted to surgery than men (71,7% vs 28,3% for TKR and 55,7% vs 44,3% for THR). Mean hospitalizations costs per patient was $BRL4,203 (SD $BRL2,115) and $BRL4,130 (SD $BRL2,145) for TKR and THR respectively. When comparing expenses according to procedures groups, prostheses represented 76,9% and 76,8% of total costs in  2009 and 2010 respectively, followed by health care professionals. CONCLUSIONS: More than 40,000 total arthroplasty surgeries were performed in SUS from January 2009 until March 2011, when THR accounted for approximately 70% of all cases. Mean age for patients submitted to surgery were similar for both procedures, being women more frequently undertaking surgery than man. When considering all costs associated to arthroplasty, total expenses were similar in both groups. However, when compared with costs reported at the private system (described elsewhere), expenses in SUS represents about 12%.