Objectives: There is a functional relationship between the hip joint and the pelvic floor muscles. In patients with secondary osteoarthritis of the hip, urinary incontinence is also seen. Research has shown that total hip arthroplasty (THA) surgery improves the symptoms of urinary incontinence. This prospective cross-sectional study without a control group was performed on THA candidates with urinary incontinence and secondary osteoarthritis with the aim of investigating the effect of THA with a direct lateral approach and subsequent routine physiotherapy on the symptoms of urinary incontinence.Methods: Sampling was performed using a simple method among those referred to orthopedic clinics in the private sector. Data were collected in all patients before and 3 months after THA using demographic, International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and hip range of motion record tables. The results are presented as mean with standard deviation.Results: In this study, 16 men with a mean age of 76.75 years (±4.65) and 8 women with a mean age of 72.75 years (±7.32) participated. Before THA, stress urinary incontinence (54.16%) and urgency urinary incontinence (20.83%) had the highest frequency. However, after THA, the frequency of stress and urgency urinary incontinence decreased (16.66% and 8.33%, respectively). According to the results of the ICIQ, complete improvement of urinary incontinence symptoms was observed in up to 62.5% of the subjects. After THA, there was a significant difference between the mean total score obtained from the WOMAC questionnaire compared to before surgery. There was a significant improvement in the range of motion of the hip joint in all directions.Conclusions: THA and routine hip physiotherapy in patients with urinary incontinence and secondary hip osteoarthritis have a significant positive effect on improving symptoms of urinary incontinence and hip function. In addition, it significantly improves the ICIQ and WOMAC questionnaire scores.