Secondhand smoke is one of the most common toxic environmental exposures to children, and maternal health problems also have substantial negative effects on children. We are unaware of any studies examining the association of living with smokers and maternal health. To investigate whether non-smoking mothers who live with smokers have worse physical and mental health than non-smoking mothers who live in homes without smokers. Nationally representative data from the 2000–2004 Medical Expenditure Panel Survey were used. The health of non-smoking mothers with children <18 years (n = 18,810) was assessed, comparing those living with one or more smokers (n = 3,344) to those living in households with no adult smokers (n = 14,836). Associations between maternal health, household smoking, and maternal age, race/ethnicity, and marital, educational, poverty and employment status were examined in bivariable and multivariable analyses using SUDAAN software to adjust for the complex sampling design. Scores on the Medical Outcomes Short Form-12 (SF-12) Physical Component Scale (PCS) and Mental Component Scale (MCS) were used to assess maternal health. About 79.2% of mothers in the USA are non-smokers and 17.4% of them live with ≥1 adult smokers: 14.2% with 1 and 3.2% with ≥2 smokers. Among non-smoking mothers, the mean MCS score is 50.5 and mean PCS is 52.9. The presence of an adult smoker and increasing number of smokers in the home are both negatively associated with MCS and PCS scores in bivariable analyses (P < 0.001 for each). Non-smoking mothers with at least one smoker in the household had an 11% (95% CI = 0.80–0.99) lower odds of scoring at or above the mean MCS score and a 19% (95% CI = 0.73–0.90) lower odds of scoring at or above the mean PCS score compared to non-smoking mothers with no smokers in the household. There is an evidence of a dose response relationship with increasing number of smokers in the household for PCS (P < 0.001). These findings demonstrate a previously unrecognized child health risk: living with smokers is independently associated with worse physical and mental health among non-smoking mothers.