The aim of this report is to present a case of severe skin ulceration and cellulitis in a seven year old mongrel dog following cystitis. The Providencia stuartii strain was the only isolate from skin lesions. This bacterium is a Gram-negative rod belonging to the family of Enterobacteriaceae. To the best of our knowledge, even though there are some reports in the literature concerning animal infections with Providencia species, there have been no cases of cellulitis in which this pathogen is involved. The Providencia stuartii strain was highly sensitive to amikacin, and the dog responded quickly to this antibiotic.