This study was conducted to compare the date on knowledge, attitude and motivation toward blood donation between donors and non-donors. The study population included 622 donors and 322 non-donors who visited the mobile blood donation car of Taegu Red Cross Blood Center and participated the group appointed blood donation campaign managed by the center from March 1 to March 31, 1989. The donors and non-donors were questioned above mentioned items with a formulated questionnaire. Among the general characteristics of the subjects in the study, male predominance (84.1% in donors and 73.6% in non-donors) in young age group (16-24 years) was the outstanding feature. As a medium of information about blood donation, “television” was playing a dominant role (donors; 75.2%, non-donors; 78.9%), while “magazine” played more important roles among donors. Of the donors, 70.6% and of the non-donors, 58.1 replied that they had ever been induced to donate blood (p<0.01). Major inducers were friend and personnel of mobile blood donation vehicle. On the measuring of knowledge level, the average rates of correct answer was higher in donors (62.6%) than in non-donors (54.1%) (p<0.01). Higher the education level was presented, higher the knowledge level (p<0.05). There have been noticeable difference between donors and non-donors in blood replying the questionnaire set to measure their attitude toward blood donation, especially in the items such as “impression toward blood”, “selection of transfusion blood source” and “view on the situation of blood shortage.” The major motivation toward blood donation of the groups were “possible future need” and “altruism or humanitarian interest”. The major reasons for not donation blood in both groups were “fear of the needle” and “dread to visit to mobile car or center”.