Health educators in schools are a very important part of the education system. Considering the significant prevalence of vitamin D deficiency in the Kingdom of Saudi Arabia, it is important to investigate the knowledge of and attitude towards vitamin D among health educators. This study aims to examine the knowledge of and attitude towards vitamin D among health educators in public schools in Jeddah as well as to identify the associated sociodemographic factors. A cross-sectional study was conducted between May and December 2021 among 231 health educators. Data were collected via a self-administered online questionnaire. The results revealed that only 45% of health educators had good knowledge of vitamin D, and approximately 43% had a positive attitude towards vitamin D. Additionally, those who had good knowledge of vitamin D were males (58.7%) (p = 0.005) and had a bachelor’s degree (74%) (p = 0.01). Moreover, male health educators aged 45–54 years had a positive attitude towards vitamin D (3.8 ± 0.7) (p = 0.007). In addition, female health educators who were divorced (3.8 ± 0.7) and widowed (3.6 ± 0.5) (p = 0.04) and those who were administrators (3.3 ± 0.7) (p = 0.01) had a positive attitude towards vitamin D. The Ministry of Education (MOE) in the Kingdom must educate health educators through educational programmes that aim to increase the knowledge of and develop a positive attitude towards vitamin D intake.