Abstract Electromagnetic radiation is the fastest growing environmental factor due to the vast development in technology in the last decades. Awareness about radiation has received more attention worldwide due to its health hazards. Adolescents are exposed to radiation from various sources on a daily basis. The number of studies conducted to assess the knowledge and perception of adolescents and young adults regarding radiation and its risks is limited, especially in the Middle East. The aim of this study was to assess the knowledge and perception about radiation and its associated hazards among adolescents and young adults. Additionally, our aim was to identify the best methods of education regarding radiation and its protective measures. A cross-sectional study was conducted among 506 participants in Saudi Arabia. It was found that the overall knowledge and awareness on radiation sources and its hazards among adolescents and young adults is inadequate. The majority of participants had misconceptions regarding radiation sources and its detriments to health. Socio-demographic variables were associated with the participants’ perception. Educating adolescents on radiation and its safety measures is much needed. It was found that the most preferred methods of education are social media and health care providers. The findings of this study will provide insight when designing future interventions to promote specific messages to enhance knowledge and improve awareness regarding radiation.