Warts are the most common viral infections caused by human papillomavirus. Although there is no definite treatment for them, new treatments which are safe, cost benefit, and easy to use will help to improvement of patients. To compare efficacy and safety of 15% potassium hydroxide (KOH) solution versus cryotherapy in the treatment of common warts. A total of 34 patients with common warts diagnosed by a dermatologist were enrolled in this openlabel therapeutic trial. The common warts in the right-sided (hand or foot) were treated with cryotherapy while leftsided lesions treated with 15% KOH solution. The patients were evaluated at every week after the treatment to assess the cure rate and adverse events. Mean time of improvement was 34 and 29 days using cryotherapy and 15% KOH solution, respectively. This demonstrated a statistically significant difference (P =0.001). Also, adverse events including pain, erythema, ulcer, and necrosis were less in KOH group than cryotherapy one which it was statistically significant (P<0.05). Our results demonstrated that 15% KOH solution might be effective with low adverse events in the treatment of common warts. Further clinical studies with the applied concentration and larger sample size are warranted.