Objective: Overactive bladder (OAB) symptoms are due to detrusor over activity (DOA) which is characterized by involuntary detrusor contractions during bladder filling. It may co-exist with BOO due to benign prostate hyperplasia (BPH) in men. Hence, the study was designed to assess and compare the clinical efficacy of combination therapy of anti-muscarinics with α-blockers versus α-blockers monotherapy in BPH patients with OAB. Methods: This study was carried out in the urology department of a tertiary care hospital for a period of 4 months. Clinical and biochemistry reports of 90 patients were collected in designed case report forms. All statistical analyses were performed using IBM Statistical Package for Social Sciences 17 and Graph Pad Prism 7.0. Results: The perceived change from baseline values was comparatively better in patients who received combination of tamsulosin with tolterodine than other two groups. All the three groups were effective in reducing the symptoms. Conclusion: Tamsulosin with tolterodine at a recommended dosage has shown to be clinically more effective than oxybutynin after 12 weeks of treatment for men with OAB in BPH. Patients with increased urinary retention risk should be carefully monitored during the course of treatment.