Background: Organ donation is a lifesaving procedure for inpatients with end-stage organ failure. It has two types: organ taken from a live donor and cadaveric organ donation after death. Blood donation is also significant in saving lives, KSA mainly provides the blood transfusion facility basically in hospital-based blood banking system, so it is accessible by everyone. Objectives: To assess the perception and attitude among adults attending primary health care centers in Al-Madinah regarding blood and organ donation to formulate a base for further educational interventions to improve the perception towards blood and organ donation among them. Methodology: This was a cross-sectional study conducted at primary health care centers in Al-Madinah, Saudi Arabia. A total 670 adult participants completed a self-administrated questionnaire concerning blood and organ donation. Results: Out of 670 adult participants, 69.3% were males with the mean age of (35±8.77). The majority of the respondents (83.1%) were with a university degree or more and 95.4% lived in urban areas. Over half of them (58.2%) did not donate blood before and (65.2%) depended on friends and family to get information about blood donation. Our results showed a high knowledge level among the population regarding blood donation, and it was significantly associated with the educational level (P=0.000) and occupation (P=0.000). Whereas, more than half of the population (57.7%) said that no one ever asked them to donate blood. The respondents showed poor knowledge about organ donation, and as a consequence, most of them showed negative attitudes. Only 1.6% of the participants had a history of organ donation either as a donor or recipient, 16.6% were willing to donate their organs before death and 32.2% want to donate their organs after death. Conclusion: This study found a high knowledge levels among the population, with more negative attitudes towards blood donation. Generally, the knowledge regarding organ donation was relatively poor. Their attitudes regarding organ donation and transplantation established a significant hesitancy, and young participants and highly educated people showed more positive attitudes. So, we recommend holding more physical campaigns in vital institutions to encourage people to donate blood. The Ministry of Health should hold health education and awareness sessions and campaigns to support the knowledge, attitudes, and beliefs of the public towards organ and blood donation.