Maternal undernutrition remains a leading cause of morbidity and mortality in Nigeria. Yet, most interventional programmes are focused on infant and child nutrition outcomes and not on maternal nutrition-related outcomes. Evidence suggests that the integration of household environmental interventions into nutrition actions can make a difference in reducing the burden of maternal undernutrition. This study examined the influence of household environmental conditions (HHEC) on the nutritional status of women of childbearing age in Nigeria using secondary data from the 2013 Nigeria Demographic and Health Survey. The original sample of 38,948 women age 15-49 years was selected using multi-stage probability sampling. The sample for the current analysis was 23,344 after exclusion of women due to health status or provision of incomplete information. The dependent and main independent variables were undernutrition (defined as Body Mass Index below 18.5) and HHEC (generated from cooking fuel, toilet type, source of drinking water, and housing materials) respectively. Data were analysed using descriptive statistics, Chi-square, and logistic regression model at 5% level of significance. The prevalence of undernutrition among women living in houses with unimproved and improved HHEC was 17.2% and 7.2% respectively. The adjusted odds of undernutrition was significantly higher among women who lived in houses with unimproved HHEC (aOR = 2.02, C.I = 1.37-2.97, p <0.001). The odds of undernutrition are greater in young women (aOR = 2.38, C.I. = 1.88-3.00, p <0.001) compared to older, and those of lower wealth status (aOR = 2.14, CI = 1.69-2.71, p <0.001) compared to higher. Other predictors of undernutrition in women of reproductive age in Nigeria include the level of education, marital status, and working status. Living in a house with unimproved environmental conditions is a predictor of undernutrition in women. The integration of environmental and nutrition programmes could assist in addressing this burden in Nigeria.