BACKGROUND: The methicillin-resistant Staphylococcus aureus (MRSA) pediatric osteomyelitis and septic arthritis have been associated with more complications than other organisms. However, there is no large sample study available to provide data of causative organisms. METHODS: We performed a retrospective chart review study from 2003-2017 (15 years) records with diagnosis codes for osteomyelitis and septic arthritis in patients from age 0 to 18 years who underwent surgery in form of debridement or incision and drainage. We explored culture and organism reports to find out presence of MRSA. We compared the prevalence of MRSA in patients who underwent single surgery with patients who underwent more than one surgeries. RESULTS: A total of 753 patients were included. Patients with follow up less than one year and incomplete data were excluded. Of these, 22.84% (172/753) patients were culture positive for MRSA. In a group of multiple washout patients, prevalence of MRSA was 50.92% (55/108). In the other group of single procedure patients, prevalence of MRSA was 18.13% (117/645). The relative risk of multiple surgery in MRSA positive patients were 4.42 (p<0.001) as compared to MRSA negative patients. CONCLUSION: Our study confirms that MRSA is the single most indicator for adverse clinical outcome in pediatric bone and joint infections. Excluding the patients who were never treated surgically is definitely the limitation of this study. We strongly recommend MRSA antibiotic treatment in all pediatric patient with bone and joint infection and it should not be delayed until operative cultures are obtained. LEVEL OF EVIDENCE: Level III.