BackgroundWhether diet has beneficial effects on cardiovascular disease (CVD) in childhood cancer survivors as in the general population is unknown. Therefore, we examined associations between dietary patterns and risk of CVD in adult survivors of childhood cancer.MethodsChildhood cancer survivors, 18–65 years old in the St Jude Lifetime Cohort (1882 men and 1634 women) were included in the analysis. Dietary patterns were defined by the adherence to the Healthy Eating Index (HEI)–2015, Dietary Approaches to Stop Hypertension (DASH), and alternate Mediterranean diet (aMED) based on a food frequency questionnaire at study entry. CVD cases (323 in men and 213 in women) were defined as participants with at least one grade 2 or higher CVD-related diagnosis at baseline. Multivariable logistic regression adjusted for confounders was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of CVD.ResultsGreater adherence to HEI-2015 (OR=0.88, 95% CI: 0.75–1.03, per 10 score increment), DASH (OR=0.85, 95% CI: 0.71–1.01, per 10 score increment), and aMED (OR=0.92, 95% CI: 0.84–1.00, each score increment) were, albeit trending towards significance, associated with a lower risk of CVD in women. HEI-2015 was associated with a non-significantly lower risk of CVD in men (ORQ5 vs. Q1=0.80, 95% CI: 0.50–1.28). These dietary patterns were also associated with a lower risk of CVD in survivors with high underlying CVD risk.ConclusionsAs recommended to the general population, a diet rich in plant foods and moderate in animal foods needs to be a part of CVD management and prevention in childhood cancer survivors.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12916-023-02956-x.