Accumulating evidence suggests that vitamin D deficiency and insufficiency may play a role in the development of coronary heart disease (CHD) and associated risk factors. Saudi Arabia has witnessed a growing epidemic of CHD and associated risk factors during the last few decades for several reasons, including the rapid changes in lifestyle and urbanization. Furthermore, national studies have demonstrated that vitamin D deficiency is highly prevalent in Saudi Arabia. Thus, it is crucial to examine the function of vitamin D in the prevention of CHD in Saudi Arabia. Therefore, the aim of this study was to examine the association between vitamin D status and the risk of CHD among adults in Saudi Arabia. It also examined the association between vitamin D deficiency and cardio-metabolic risk factors, including obesity, diabetes, hypertension and hypercholesterolemia, among subjects with and without CHD in Saudi Arabia. In addition, the present study attempted to compare the levels of knowledge, attitudes and behaviours related to vitamin D between subjects with and without CHD. It also examined the association of vitamin D status with knowledge, attitudes and behaviours related to vitamin D among study subjects. A qualitative approach was used in this study to further understand of study subjects’ knowledge about vitamin D and attitudes toward sun exposure. It also explored the social and cultural factors which may explain for the high prevalence of vitamin D deficiency in Saudi Arabia.