ABSTRACT The aim of this study was to investigate the relationship between food consumption of 99 pregnant women aged 16-44 years who gave birth at a maternity hospital in Rio de Janeiro and newborn birth weight. Maternal consumption of unprocessed or minimally processed and ultra-processed foods was evaluated through the Food Consumption Markers Form. For ultra-processed foods, most pregnant women regularly consumed sweets (73.7%), soft drinks (71.7%), sausages (65.7%), salted crackers (63.6%) and fried foods (55.6%). Among unprocessed or minimally processed foods, most pregnant women consumed beans (85.9%) and milk or yogurt (60.6%), while less than half consumed fruits (44.4%), raw vegetables (28.3%) and cooked vegetables (27.3%) regularly. Among newborns, 13.5% presented low birth weight. There was a significant relationship between consumption of sausages (p= 0.02) and sweets (p= 0.04) by pregnant women and low birth weight of newborns. Maternal consumption of sausages increased the odds of newborn low birth weight (OR 1.46, 95% CI 1.02-2.10).