Background The use of radiological examination is increasing worldwide. Since radiation exposure can result in many health hazards, medical professionals, as well as medical students, should possess adequate knowledge regarding radiation and its related hazards to protect themselves and the patients. Many studies have assessed medical students’ knowledge on this topic, but never in Palestine. In this study, we aimed to examine Palestinian medical students’ awareness and knowledge regarding radiological examination modalities and their risks on themselves and their patients. Methods This was an observational, cross-sectional, population-based study, conducted to assess the awareness of radiation exposure and its risks among Palestinian medical students. An online questionnaire was implemented on medical students at An-Najah National University. A total knowledge score that ranged from 0 to 22 was calculated for each participant, with higher scores indicating better knowledge regarding radiation doses and the related hazards. Results Two hundred eighty and seven students participated in our study, with a response rate of 71%. The average knowledge score of the participants was 10.97 ± 4.31 out of a maximum of 22 points. Male participants and participants in advanced study years achieved better knowledge scores (p-values were 0.034 and < 0.001, respectively). Perceived radiology knowledge was significantly associated with the actual knowledge score among the participants (p-value< 0.001). Receiving radiology lectures in fourth and fifth years significantly affected the participants’ knowledge score (p-values were < 0.001). Conclusions We found a severe lack of knowledge regarding radiation doses and related risks among medical students. Therefore, we recommend that medical schools update and supplement their curriculum regarding knowledge on radiation.