Vitamin D deficiency has been recognized as a worldwide epidemic, affecting even healthy population. The awareness and practices of primary health care physicians regarding vitamin D needs to be highlighted, as improving the knowledge of physicians will improve the knowledge of the public as a whole. This study aimed to address the knowledge, attitude and practice of primary health care physicians regarding vitamin D in Riyadh city, KSA. A cross-sectional study was conducted using a self-administered questionnaire among primary care physicians; currently working in Riyadh city, KSA. Descriptive statistics: mean, standard deviation, frequencies, percentage were calculated. Of the 158 eligible participants, there were 43.7% male. The mean participant's age of was 40.7 ± 9.6 years. Of all the participants; 51.3% showed good knowledge regarding vitamin D, while 48.7% showed poor knowledge; 55.1% had positive attitude. Participants were asked about patient features that would alert them to vitamin D status. Fatigue was shown to alert more male than female physicians participants (75.4% vs. 58.4%, p = 0.026). Participants were asked about ways of managing vitamin D deficiency. Nutrition advice was mostly given by older physicians (p = 0.044) and non-Saudis (p = 0.003). In conclusion, this survey identified a gap in knowledge and practice among Primary Health Care physicians. The confusion could be partly attributed to different guidelines and sources of information. This study showed that continuous medical education and online sources were the most common sources of information about vitamin D among physicians.