Objective: To assess racial differences in body mass index (BMI) change over 5 years among people with spinal cord injury (SCI). Design: Multicenter longitudinal study. Setting: Spinal Cord Injury Model Systems centers. Participants: Individuals (N=437; 313 non-Hispanic white, 81 non-Hispanic black, and 43 Hispanic; 335 men; mean age, 41.3±13.5y) who incurred an SCI from 1974 to 2010 and completed 2 follow-up assessments within 5 years between October 1, 2006 and September 18, 2015 (mean duration of injury, 9.1±9.6y at the start of the 5-year follow-up). Interventions: Not applicable. Main Outcome Measures: BMI (in kilograms per meters squared). Results: The mean BMI of 437 participants increased from 26.4±6.3 to 27.0±6.4kg/m2 over 5 years (P=.002). The greatest increase was noted for Hispanics (2.0±5.7kg/m2; P=.02), followed by non-Hispanic whites (0.6±3.9kg/m2; P=.01) and non-Hispanic blacks (0.01±3.7kg/m2; P>.99). The differences in BMI increase across racial groups were significant (P=.03) in those with paraplegia (American Spinal Injury Association Impairment Scale A, B or C), those who were underweight or of normal weight at baseline, and those within 10 years of their injury. Such racial differences remained significant after taking into account demographic and injury characteristics. Conclusions: Our study findings provide a foundation for future research to explore risk and protective factors that contribute to racial differences in weight gain after SCI, which help alert health care professionals to a high-risk group for obesity prevention and management.