Blastomycosis is a rare mycotic infection in Africa. Isolated cutaneous disease is extremely rare. We report three cases of cutaneous blastomycosis confirmed by istologic and mycologic examination. No visceral involvement was found. Blastomycosis is rare in Tunisia. The most common site of involvement is the lung. The three cases reported presented with skin involvement only, suggesting a cutaneous inoculation of Blastomyces dermatitidis. The diagnostic criteria of cutaneous blastomycosis are discussed.