Deficits in child growth are associated with poor cognitive outcomes and an increased risk for infection and mortality globally. One hundred forty million people are chronically exposed to arsenic from contaminated drinking water worldwide. While arsenic exposure has been associated with cognitive developmental delays in children, there is limited research on the association between arsenic exposure and growth deficits in young children. The objective of this study was to assess the association between chronic arsenic exposure and deficits in growth among children under 5 years in a rural setting in Bangladesh. Urinary arsenic measurements were collected from 465 children between the ages of 28 days–59 months in rural Matlab, Bangladesh, and analyzed by graphite furnace atomic absorption. Height and weight measurements were collected from children according to World Health Organization child growth standards. A z-score cutoff2 standard deviations below the mean was used to define stunting (height-for-age z-score), underweight (weight-for-age z-score), and wasting (weight-for-height z-score). Children under 5 years with urinary arsenic concentrations in the third tertile (greater than 31 μg per liter (μg/L)) had a two times higher odds of being underweight after adjustment for age, creatinine, paternal education, breastfeeding, number of individuals using the same sleeping room, and physician-diagnosed pneumonia (Odds Ratio (OR): 2.29 (95% Confidence Interval (CI): 1.16, 4.52)). Children under 2 years of age had a two times higher odds of being wasted after adjustment for age, creatinine, paternal education, breastfeeding, number of individuals using the same sleeping room, and physician-diagnosed pneumonia (OR: 2.85 (95% CI: 1.18, 6.89)). These findings suggest that arsenic exposure is associated with an increased odds of being wasted and underweight among young children in rural Bangladesh. •Over fifty million children are estimated to be wasted globally.•Deficits in child growth are associated with poor cognitive outcomes and mortality.•Arsenic exposure was associated being wasted and underweight among young children.