Background: Little is known about the prevalence of secondhand smoke exposure (SHSe) among cancer survivors. We sought to determine the prevalence, trends, and correlates of SHSe among nonsmoking adult cancer survivors in the United States. Methods: Interview and serum cotinine data for nonsmoking adults, age 20 years and older, with a history of cancer (N = 686) were obtained from consecutive two-year cross-sectional cycles of the National Health and Nutrition Examination Survey from 1999 to 2012. SHSe was defined as serum cotinine 0.05-10 ng/mL among nonsmokers. We calculated and trended the prevalence of SHSe among nonsmoking cancer survivors. Multivariable logistic regression was used to examine the associations of SHSe with sociodemographic, smoking, and clinical characteristics. Survey weights were applied in estimating prevalence rates, adjusted ORs, and confidence intervals (CI). Results: The weighted aggregate SHSe and self-reported indoor SHSe prevalence rates over the study period were 28.26% (95% CI: 24.97%-31.55%) and 4.53% (95% CI: 3.48%-5.57%), respectively. SHS exposure declined from 39.61% (95% CI: 27.88%-51.34%) in 1999/2000 to 15.68% (95% CI: 9.38%- 21.98%) in 2011/2012 (Ptrend < 0.001). Age ≥ 60 years was protective against SHSe, while being black, having less than high school education, poverty, and a smoking-related cancer history were associated with higher odds of SHSe. Conclusions: Fortunately, SHSe among nonsmoking cancer survivors in the United States is on the decline, although certain subgroups remain disproportionately burdened. Impact: These findings highlight clinical and public health imperatives to target socioeconomically disadvantaged nonsmoking cancer survivors to reduce their SHSe. Cancer Epidemiol Biomarkers Prev; 26(8); 1296-305.