Objectives: Between 20 to 50% of medical imaging examinations are considered inappropriate, and unnecessary ionizing radiation exposures may lead to cancer. We hypothesized that Bahraini patients who self-present for ionizing radiation procedures are not aware of, and lack the requisite knowledge of, the inherent risks associated with their use than patients prescribed for diagnostic purposes. We attempted to examine and compare the awareness and knowledge of the associated risks of ionizing radiation in common diagnostic radiological procedures between prescribed and self-presenting patients in Bahrain. Methods: A cross-sectional survey was carried out among 416 Bahraini patients attending the radiology department of the Salmaniya Medical Complex (SMC), a secondary health care center, who had been referred by primary care physicians or self-presented to the center. Data was collected via face-to-face interviews. Results: Prescribed patients (n = 358) had a better awareness than self-presenting (n = 58) patients on all ionizing radiation awareness statements (i.e., risks, permissible levels, willingness to undergo the procedure, and preference for a clinical examination over a radiological procedure) (p < 0.050). Of the 10 knowledge statements, the prescribed patients agreed on four statements than the self-presenting patients: preventing or minimizing exposure improves health, people can prevent or minimize exposure, a lifelong health concern, and radiological procedures offer best diagnoses compared to medical tests or procedures (p < 0.050). Conclusions: Bahraini patients who reported to SMC lack awareness and knowledge on ionizing radiation. The proportion of appropriate responses to awareness and knowledge questions were paltry for self-presenting patients and deficient for the prescribed patients in the knowledge segment alone. © 2017, Oman Medical Specialty Board. All rights reserved.