Background: Corynebacterium striatum is part of the normal flora of the skin, oral cavity, and intestine. However, it can be a pathogen causing endocarditis, pneumonia, arthritis, and meningitis occasionally. We evaluated the clinical features and antimicrobial susceptibility pattern of C. striatum cases. Methods: Patients infected with C. striatum, who consulted infectious disease physicians and were admitted to Hanyang University hospital between January 2018 and January 2021, were enrolled for an antimicrobial susceptibility test (AST). We reviewed medical records of selected patients for information on diagnosis, specimen types, and antibiotics used before and after AST. AST was performed using E-test and interpreted according to the Clinical and Laboratory Standards Institute M45 guidelines. Results: A total of 23 cases were evaluated, and average age of patients was 58.5 years. Ten cases were diagnosed sepsis. Eight cases were complicated with cancer, and five cases had wound infections. Four cases were treated with vancomycin prior to AST; in 13 cases, antibiotics were switched to vancomycin after AST. Resistance rates were highest for ciprofloxacin (93.3%), which was followed by cefotaxime (92.3%), penicillin G (87.0%), erythromycin (87.0%), trimethoprim/sulfamethoxazole (78.3%), and meropenem (76.5%). Conclusion: The patients infected by C. striatum were old and immunosuppressed, while many had cancer. Since C. striatum shows resistance to most drugs except vancomycin, we should consider conducting AST prior to antibiotic treatment.