Medical records of 5 cats with blastomycosis examined at the University of Tennessee Veterinary Teaching Hospital from 1979 to 1986 were reviewed. Clinical signs of blastomycosis varies depending on the organ(s) affected, but respiratory tract disease was most common, followed by CNS signs and ocular problems. A definitive diagnosis was made by identification of characteristic fungal organisms in biopsy or necropsy specimens. Two cats treated with amphotericin B did not respond to treatment and died or were euthanatized. The lungs, brain, eyes, and lymph nodes commonly were affected, but one cat had only cutaneous and regional lymph node involvement. The respiratory tract appeared to be a common primary site of infection, with dissemination to other organ systems. The typical host response was a pyogranulomatous cellular infiltrate with numerous fungal organisms evident.