Aim: We used magnetic resonance imaging (MRI) to compare the neuroimaging of children with their first episode of clinical enterovirus 71-associated transverse myelitis (EV71-TM), myelin oligodendrocyte glycoprotein antibody positive transverse myelitis (MOG-TM), aquaporin-4 antibody positive transverse myelitis (AQP4-TM), transverse myelitis in multiple sclerosis (MS-TM), and unclassified transverse myelitis (UNC-TM). Method: We performed a retrospective blinded radiological assessment and compared the neuroimaging of 52 children (32 females, 20 males; mean age 9y 8mo, SD 5y 5mo, range 5mo–17y) presenting with their first episode of myelitis caused by EV71-TM (n=11), MOG-TM (n=10), AQP4-TM (n=9), MS-TM (n=13), and UNC-TM (n=9). Results: In the EV71-TM group, lesions were distributed throughout the cord and enhancement of nerve roots (ventral and dorsal) was common. The MOG-TM group had lesions distributed throughout the cord and most commonly longitudinally extensive transverse myelitis and lesions involving the grey matter alone on axial scans. The AQP4-TM group had lesions distributed in the cervicothoracic spine, cavitation, and contrast enhancing lesions. All patients with AQP4-TM had an abnormal brain MRI scan. The MS-TM group characteristically had multiple short segment lesions of the cord involving the cervicothoracic spine. The UNC-TM group did not have distinctive spinal MRI findings but had a relative paucity of lesions on their brain MRI scans. Interpretation: There are neuroimaging findings that are helpful in differentiating between myelitis associated with EV71, MOG, AQP4, and multiple sclerosis in children. These features may be useful early in the presentation of transverse myelitis while awaiting infectious/immunological testing, and/or further demyelinating events. What this paper adds: Magnetic resonance imaging can help identify aetiologies for children presenting with a first episode of myelitis. Entervirus-71-associated myelitis lesions are distributed throughout the cord and enhancement of nerve roots is common. Lesions distributed throughout the cord are commonly seen in myelin oligodendrocyte-associated myelitis. Aquaporin-4-associated myelitis lesions are distributed in the cervicothoracic spine, cavitation and contrast enhancing lesions are common. Short segment lesions in the cervicothoracic spine are commonly seen in multiple sclerosis-associated myelitis.