This study explored the association between child undernutrition and household environmental quality in urban and rural households. Anthropometric assessments were conducted on 370 preschool children in three urban communities (high, medium and low-density) and one rural community. A structured questionnaire for mothers and an observation checklist were used to collect sociodemographic and environmental data. An Environmental Quality Index (EQI) combining four composite indicators of household environment (water, sanitation, housing, waste disposal/drainage) was developed. Results Overall prevalence was 16.8% for wasting, 29.7% for stunting and 28.4% for underweight. There was a significant association between the EQI and stunting (r = -0.437, p =0.000) and also, underweight (r = -0.491, p = 0.000) but not with wasting (r = -0.152, p =0.201). Dissagregation of data into rural and urban revealed that the significant associations disappeared in the rural but persisted among the urban children. The findings reiterate the significance of environmental inadequacies to childhood undernutrition. However, environmental quality appears to be a more important determinant of undernutrition among urban than rural children.