Although it has long been used as a topical treatment of pityriasis versicolor (PV), the efficacy of topical selenium disulfide as compared to topical ketoconazole in the treatment of PV remains unclear. This study aims to assess the mycological efficacy and safety of SeS 1.8% shampoo and ketoconazole 2% shampoo for the treatment of PV.. A double-blind randomized controlled trial was performed in patients with PV during September-December 2018, based on block randomization. Physical examinations, scale provocation test, Wood’s lamp, and potassium hydroxide examination were conducted. Intention to treat analysis was performed to evaluate the mycological efficacy.. The mycological efficacy and side effect were not significantly different between the ketoconazole group and the selenium group; 94% vs 86% (RR=2.3(95%CI 0.6-8.5), p=0.182), and 22% versus 8%.. SeS2 1.8% has the same mycological efficacy and side effect as compared to ketoconazole 2% in the treatment of PV.