Fish tank granuloma has traditionally been associated with Mycobacterium marinum. We report the case of a 54 old-year woman that worked in a freshwater fish pet store and developed a skin ulcer in a hand finger with a suppurative granuloma secondary to Microbacterium paraoxydans. This is a bacterial fish pathogen, rarely observed in human infections. Identification was performed by colony morphology and MALDI-TOF. She evolved satisfactorily after receiving a sequential treatment with beta-lactams and linezolid. To our knowledge, it is the first known description of this type.