Background:As neonatal care improves in low-resource settings, more preterm or low birth weight (LBW) babies are surviving, but little is known about their long-term outcomes. Globally, preterm and/or LBW babies are at increased risk of mortality, malnutrition, and developmental delay.Objectives:We aim to describe the differences in development in rural Rwandan children at 24–36 months of age born preterm and/or LBW compared to their peers born term or normal birth weight (term/NBW), and to assess factors associated with poor development.Methods:We conducted a cross-sectional study using secondary data analysis from two combined datasets from 2014, using Ages and Stages Questionnaire (ASQ-3) for developmental assessment and anthropometrics for nutritional status (stunting and wasting). Demographic and clinical factors associated with poor developmental outcomes in univariate regression at α = 0.20 were included in a full model; we used backward stepwise penalized multivariable logistic regression to identify a final model at α = 0.05.Findings:In total, 445 children were included; 405 term/NBW, and 40 preterm and/or LBW. Half of them (n = 234; 52.6%) had developmental delay, including 207 (51.1%) among term/NBW and 27 (67.5%) among preterm and/or LBW (p = 0.048). In the final model, term/NBW children with stunting alone had a significant increase in the odds of developmental delay (OR 2.05, 95% CI 1.37–3.07), and children with wasting had a borderline statistically significant increased odds of developmental delay (OR 5.79, 95% CI 0.98-34.39). Being preterm and/or LBW and not stunted completely predicted delay.Conclusion:Half of the children had developmental delay in our sample from rural Rwanda. Preterm and/or LBW infants were more likely to have developmental delay, and the main predictor of developmental delay was stunting, with high rates of stunting observed also in term/NBW infants. Interventions to reduce undernutrition and prevent prematurity and LBW, alongside investments to promote early stimulation for optimal development, are needed if gains in addressing developmental delay are to be made.