The most common cause of cellulitis is streptococci. Coagulase-negative staphylococci and gram-negative bacteria, such as Serratia spp., Proteus spp., and other Enterobacteriaceae may produce cellulitis in the immunocompromised patient. We report a case of Citrobacter diversus-induced cellulitis, resembling streptococcal infection, in a patient with multiple myeloma.