OBJECTIVE We aim to investigate the impact of ideal cardiovascular health metrics (ICVHMs) on the association between famine exposure and adulthood diabetes risk. RESEARCH DESIGN AND METHODS This study included 77,925 participants from the China Cardiometabolic Disease and Cancer Cohort (4C) Study who were born around the time of the Chinese Great Famine and free of diabetes at baseline. They were divided into three famine exposure groups according to the birth year, including nonexposed (1963-1974), fetal exposed (1959-1962), and childhood exposed (1949-1958). Relative risk regression was used to examine the associations between famine exposure and ICVHMs on diabetes. RESULTS During a mean follow-up of 3.6 years, the cumulative incidence of diabetes was 4.2%, 6.0%, and 7.5% in nonexposed, fetal-exposed, and childhood-exposed participants, respectively. Compared with nonexposed participants, fetal-exposed but not childhood-exposed participants had increased risks of diabetes, with multivariable-adjusted risk ratios (RRs) (95% CIs) of 1.17 (1.05-1.31) and 1.12 (0.96-1.30), respectively. Increased diabetes risks were observed in fetal-exposed individuals with nonideal dietary habits, nonideal physical activity, BMI >= 24.0 kg/m(2), or blood pressure >= 120/80 mmHg, whereas significant interaction was detected only in BMI strata (Pfor interaction = 0.0018). Significant interactions have been detected between number of ICVHMs and famine exposure on the risk of diabetes (Pfor interaction = 0.0005). The increased risk was observed in fetal-exposed participants with one or fewer ICVHMs (RR 1.59 [95% CI 1.24-2.04]), but not in those with two or more ICVHMs. CONCLUSIONS The increased risk of diabetes associated with famine exposure appears to be modified by the presence of ICVHMs.