Background: Disruptions of daily life activities during the CVOID-19 pandemic have adversely affected cancer-prevention behaviors. Socioeconomic status (SES) impacts on changes in cancer prevention behaviors have not been fully investigated. To tackle this gap, we examined the effects of SES on COVID-19 related changes in cancer prevention behaviors. Methods: We invited participants from previous studies conducted at the Ohio State University Comprehensive Cancer Center who agreed to be re-contacted to participate in a survey assessing the impact of COVID-19 on various behaviors between June and November 2020. Participants reported current cancer prevention behaviors, including physical activity, daily fruit and vegetable intake, alcohol consumption, and tobacco use. In addition, participants reported qualitative changes in current behaviors relative to pre-COVID levels. We combined current behaviors with COVID-related changes to construct a 24-point cancer prevention score. Participants were classified into low, middle, or high SES based on household income, education, and employment status. Adjusted multinomial logistic regression was used to examine the association between SES and COVID-19 related changes in cancer prevention behaviors. Results: The study sample included 6136 eligible participants. The average age was 57 years, 67% were female, 89% were non-Hispanic White, and 33% lived in non-metro counties. The proportion of participants in the lowest cancer prevention behavior quartile decreased significantly with higher SES [low SES vs. high SES; 32% vs. 28%; P-value <.001]. Relative to pre-COVID-19 levels, higher SES was significantly associated with increases in post-COVID-19 prevalence of more physical activity [low SES vs. high SES; 12% vs. 28%; P-value <.001], higher fruit and vegetable intake [low SES vs. high SES; 12% vs. 14%; P-value <.001], and more alcohol consumption [low SES vs. high SES; 15% vs. 22%; P-value <.001]. Higher SES was associated with lower tobacco use prevalence [low SES vs. high SES; 5% vs. 2%; P-value <.001]. Relative to the highest prevention score quartile, the adjusted odds of scoring in the lowest prevention score quartile were: adjusted odds ratio (aOR) 1.55 (95% CI: 1.27 - 1.89) and aOR 1.40 (95% CI: 1.19 - 1.66), respectively higher for low and middle SES. Low SES was significantly associated with higher odds of less frequent physical activity (aOR = 1.87; 95% CI: 1.49 - 2.35) and less fruit and vegetable consumption (aOR = 1.56; 95% CI: 1.15 - 2.12). Middle SES relative to high SES was associated with lower odds of more alcohol consumption (aOR = 0.64; 95% CI: 0.49 - 0.85) and higher odds of binge drinking (aOR = 1.32; 95% CI: 1.09 - 1.59). Conclusions: The adverse impacts of COVID-19 on cancer prevention behaviors were seen most in those with lower SES. Public health efforts are currently needed to promote cancer prevention behaviors, especially amongst lower SES adults.