The primary objective of this study is to examine the disparities in childcare and infant feeding practices by family structure (single-mother vs. two-parent households) and whether household income level may modify the observed associations by family structure. The cross-sectional data analysis was conducted using a nationally representative sample of children aged 0 to 2 years enrolled in the 2007 National Survey of Children's Health. The analytic sample is children from single mothers (n = 1801, 16.0%) and children from two parents (n = 11 337, 84.0%). Children of single mothers used more non-parental childcare [adjusted odds ratios (AOR) = 2.67, 95% confidence intervals (CI) = 1.99-3.58], especially relative care and centre care, than children of two parents. Lower rates of any breastfeeding for 6 months (AOR = 0.57, 95% CI = 0.43-0.77) and ever breastfed (AOR = 0.66, 95% CI = 0.50-0.89) were reported among children of single mothers than those of two parents. The many observed differences in childcare arrangements and breastfeeding by family structure remained significant in both low-and high-income households. However, children of low-income single mothers had more last-minute changes of childcare arrangement (AOR = 2.34, 95% CI = 1.55-3.52) than children of low-income two-parent households and children of high-income single mothers had more early introduction of complementary foods (AOR = 1.92, 95% CI = 1.12-3.29) than children of high-income two-parent households. This study documented disparities in childcare arrangements and infant feeding practices by family structure, regardless of income level. These findings support the need to for comprehensive policies that address maternal employment leave, childcare support and workplace accommodations and support for breastfeeding for children 0 to 2 years, especially among single mothers, regardless of income.