Arcanobacterium haemolyticum can cause deep infections, including osteomyelitis. In this study, an automated system misidentified this causal agent as Cellulomonas species but 16 s rRNA sequencing correctly identified it as A. haemolyticum. Recognizing the capability of A. haemolyticum to establish the disease is of great importance to enable accurate diagnosis and begin the suitable antibiotic therapy. Here we present the first case of successfully treated A. haemolyticum infective osteomyelitis in a 64-year-old Saudi patient with diabetes mellitus type 2 and review the characteristics of this seldom pathogenic agent.