Protothecosis is an infection caused by members of the genus Prototheca. The organisms are achlorophyllic algae that are present in different environmental niches and are globally distributed. It is a rare cause of infection in humans with majority of reported cases occurring in immunocompromised individuals. More than half of the cases manifest as cutaneous lesions. Diagnosis is by microbiological culture and/or histopathology. Response to treatment, mostly with antifungal agents, is variable. We present a 66-year-old man with type 2 diabetes mellitus, severe chronic obstructive pulmonary disease on intermittent corticosteroids, and untreated chronic hepatitis C who had a nonresolving rash. This consisted of generalized pruritic, scaly and erythematous papules, and plaques for 15 years. Subsequent skin biopsy and microbiological isolation revealed Prototheca wickerhamii. To the best of our knowledge, this is the second known case of cutaneous Prototheca infection in a patient with chronic hepatitis C.