Acute osteomyelitis is characterized, especially in children, by high morbidity due to extension of the infectious process or its chronicization. No guidelines exist for the postdischarge follow-up of children affected by acute osteomyelitis, especially regarding the utility of magnetic resonance imaging (MRI). To investigate if MRI is useful in the follow-up of AO pediatric patients. We reviewed medical records and MRI studies of children admitted to our Pediatric Department for acute osteomyelitis from 2008 to 2015. All children who had a follow-up MRI performed at least 10 days after diagnosis were included in the study. We analyzed if MRI follow-up prompted a change in patients’ treatment. A total of 28 MRI studies were performed in 27 children (13 males and 14 females). Infection involved the appendicular skeleton in 64.3% of patients. Five (18%) of these studies prompted a change in patients’ treatment. The only statistically significant indication for change in the therapeutic approach was MRI performed for persistence or worsening of the disease (p=0.0058). Change in bone signal at MRI, and time interval (more or less than 28 days) between MRI at diagnosis and at follow-up were not significantly associated with change in the patients’ treatment (p=0.40; p=0.40, respectively). Routine MRI follow-up is not useful in children affected by acute osteomyelitis who adequately respond to antibiotic treatment. It can be useful, in adjunct to clinical evaluation, in non-responders patients. Clinical monitoring remains the mainstay in the follow-up of these patients.