To examine the association between maternal body dissatisfaction and mother's (mis)perception of their infant's weight classification among families from low-income households. Mother-infant dyads were recruited during well-child visits from 2 urban primary care clinics. Maternal body dissatisfaction was measured using the Stunkard Figure Rating Scale. Perception of infant weight was assessed using a 5-point Likert scale. Infant weight-for-length percentiles were calculated using World Health Organization growth charts. Associations between maternal body dissatisfaction score and mother's (mis)perception of their infant's weight classification were examined using logistic regression allowing for nonlinear associations via restricted cubic splines. Mothers (n=180) were 26.6 ± 5.1 years old and 72% Black; infants were 8.8 ± 2.1 months old. Mean infant weight-for-length percentile was 64 ± 26. On average, mothers wanted to be one body figure smaller than their perceived current body size. Most mothers (82%) accurately perceived their infant's weight classification while few overestimated (7%) or underestimated (11%) their child's weight category. The probability of mothers misperceiving their infant's weight classification increased as maternal body dissatisfaction increased in either extreme in unadjusted (P < .05) and adjusted analysis (P=.06). Increased maternal body dissatisfaction may be associated with mother's misperception of infant weight classification. Future studies should examine this relationship in a heterogeneous population.