Polymyxin B-induced skin hyperpigmentation is a rare adverse drug reaction (ADR). In this report, we present the case of a patient who underwent an abscess resection with right epididymitis, in which a multidrug-resistant Klebsiella pneumoniae infection (KPI) is formed. The patient was treated with polymyxin B and subsequently developed skin hyperpigmentation and desquamation. The desquamation improved and the pigmentation gradually returned to normal after sixty days after the withdrawal of polymyxin B.