The American Heart Association has outlined seven modifiable cardiovascular health (CVH) metrics. However, the sex and age disparities in the association between those CVH metrics and ischemic heart disease (IHD) prevalence are unclear. Our study sought to examine the possible sex and age variations in the association between CVH metrics and IHD prevalence using an Australian nationally representative survey. We used the core sample of the 2011–2012 Australian Health Survey, and 7499 adults with fasting plasma glucose (FPG) and total cholesterol values were included. We used Poisson regression analysis to measure the associations between individual metrics and IHD prevalence. Our study used both stratification and interaction analyses to compare the magnitude of associations between sex and age groups. Then, we calculated the population attributable fractions to measure the contribution of each metric to IHD prevalence. In addition, we applied logistic regression analysis to examine the influences of ideal CVH metrics number on IHD prevalence and used stratification and interaction analyses. Body mass index, physical activity, blood pressure, and FPG have greater effects on IHD prevalence in young adults compared to older adults. We failed to detect the sex variations in CVH metrics and IHD prevalence. The ideal CVH metrics number was inversely correlated to IHD prevalence and it has similar effects in four subgroups. These CVH metrics do not explain the sex and age disparities in IHD prevalence and the topic need further explorations.