This study examined the relationship between birth weight status and a mother's social support status during her prenatal term. Using infants and mothers from the Early Childhood Longitudinal Study---Birth Cohort (n = 10,700), three types of social support were examined: father support, religiosity, and community/neighborhood support. Analysis of variance and block regression indicated that, overall, social support did not play a significant role in determining the birth weight of these infants. While certain aspects of social support were statistically significant (e.g., father attending a birth class with mother, participating in community service, and being able to ask spouse/partner for advice and help with the child) and are unarguably important for the mother to receive both during the prenatal term and following the birth of the child, the results of this study do not provide clear evidence that social support helps to predict an infant's birth weight. The limitations of the research, particularly in relation to the sample and dataset, may have contributed to the limited findings related to the major questions of this study.