Exposure to diabetes mellitus during pregnancy increases the risk of offspring obesity and cardiometabolic disease. Limited information exists regarding growth patterns among preterm infants exposed to maternal diabetes. This study describes growth differences during early childhood among late preterm infants of mothers with and without diabetes during pregnancy. In a retrospective longitudinal analysis, weight trajectories from birth to age 2 years were compared between diabetes exposure groups (N = 1554) using mixed effects modeling and adjusting for maternal and infant demographic covariates. Overall, 134 (9%) infants were exposed to diabetes (DM-group). DM-group had higher average weight (adjusted difference 300 g [95% CI: 228, 371]) and weight z-score (adjusted difference 0.67 standard deviation scores (SDS) [95% CI: 0.50, 0.84]) compared with unexposed infants. DM-group infants had accelerated weight gain from birth to discharge (adjusted weight difference 31.8 g [95% CI: 12.5, 51.1], adjusted weight z-score difference 0.07 SDS [95% CI: 0.02, 0.11]) compared with unexposed infants, including in the first postnatal week (adjusted weight gain velocity difference, day 0-3: 6.07 g/day [95% CI: 0.88, 11.25]; day 3-7: 8.37 g/day [95% CI: 1.60, 15.13]). Through age two, infants in the DM-group maintained higher average weight (adjusted difference 185.7 g [95% CI: 37.2, 334.3]) and weight z-score (adjusted difference 0.32 SDS [95% CI: 0.09, 0.55]) than unexposed infants, with greater weight gain between 18 and 24 months (adjusted difference 28.5 g/week [95% CI: 2.6, 54.4]). Maternal diabetes exposed late preterm infants had higher weight from birth to age two and greater weight gain in the first postnatal week than unexposed infants. Long term risk associated with weight trajectories in this population requires further study.