Background: Vitamin D deficiency is a common health problem in many countries, including Bahrain. However, little data exists about the awareness and the level of knowledge of vitamin D among Arab Gulf populations. Method: A cross-sectional study design was employed. A self-administered questionnaire was administered to an adult sample of 335 participants seeking information on their knowledge about vitamin D. Findings: 81.2% of the study participants had unsatisfactory total knowledge score of vitamin D. Level of education and the sources of information about vitamin D were the main significant factors that appear to influence the participants’ vitamin D awareness status. Most the participants recognized that exposure to sunlight encourages the production of vitamin D, however, only a small proportion of participants were aware of the sources of vitamin D in daily food intake and health consequences of vitamin D deficiency. Conclusion: There is inadequate knowledge and awareness regarding vitamin D deficiency among adult Bahrain population. Health campaigns are urgently needed in order to improve the community’s knowledge about the benefits and sources of vitamin D