Objectives The aim of this research is to identify whether specific aspects of the early life psychosocial environment such as quality of home and maternal‐infant interaction are associated with increased infant adiposity, in a disadvantaged population in the United States. METHODS Data on 121 mother‐infant pairs from the Albany Pregnancy and Infancy Lead Study were analyzed using three multiple linear regression models with subscapular skinfold thickness (SST), triceps skinfold thickness (TST), and weight z‐scores at 12 months of age as outcome variables. Maternal‐infant interaction was indexed by the Nursing Child Assessment Teaching Scales (NCATS) and home environment quality was indexed by the Home Observation for Measurement of the Environment (HOME). RESULTS In models including infant birth weight, cigarette use in second trimester, infant caloric intake at 9–12 months, size at birth for gestational age, infant sex, and mother's prepregnancy BMI, specific subscales of NCATs predicted infant adiposity z‐scores. Poorer mother's response to infant distress was associated with greater SST ( β = −0.20, P = .02), TST ( β = −0.19, P = .04), and weight ( β = −0.14, P = .05). Better maternal sensitivity to infant cues was associated with larger SST ( β = 0.25, P < .01), while mother's poorer social‐emotional growth fostering predicted greater SST ( β = −0.23, P < .01) and weight ( β = −0.16, P = .03). Better scores on HOME Organization of the Environment were associated with greater SST ( β = 0.34, P = .02) and TST ( β = 0.33, P = .04). CONCLUSIONS Emotionally relevant aspects of the maternal‐infant interaction predicted infant adiposity, though in different directions. This indicates that the psychosocial environment, through maternal behavior, may influence infant adiposity. However, the general home environment was not consistently related to infant adiposity.