INTRODUCTION: The impact of previous pelvic osteotomy (PO) on outcomes following conversion to total hip arthroplasty (THA) remains unclear. Our systematic review aimed to compare the outcomes of patients undergoing THA following PO to those undergoing primary THA. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a search of five online databases was performed to identify articles published between January 1, 2000, and January 1, 2024, reporting on outcomes of patients who did and did not have previous PO undergoing THA. Articles with a minimum 2-year follow-up were included. The risk of bias was evaluated through the Methodological Index for Non-Randomized Studies (MINORS) tool. A total of 17 articles reporting on 542 THAs with previous POs were included. All articles were of moderate or high quality. RESULTS: Although the data was mixed for certain outcomes, a majority of included studies demonstrated that patients who had a previous PO had similar functional outcomes and survivorship, as well as complication and reoperation rates, compared to patients undergoing primary THA. However, a history of PO resulted in consistently longer operative times, higher estimated blood loss, and less medialization of the acetabular component. CONCLUSION: Patients who had a previous PO were found to have comparable functional outcomes, complication rates, and survivorship following THA relative to controls who did not have a previous surgical history. The differences in acetabular component positioning and intraoperative outcomes allude to the increased operative complexity of conversion THA. More information is needed to determine how factors such as osteotomy type and timing between osteotomy and THA impact the evaluated outcomes.