Objective To investigate the cognition level and motivation of voluntary blood donation among residents in Dalian, in order to provide scientific theoretical direction for the publicity and sustainable development of voluntary blood donation work. Methods A total of 9 000 residents were selected from 10 districts, 4 universities and 4 institutions through stratified random sampling method from January to June 2014 in Dalian. The questionnaire was self-designed according to Blood Donation Law of the People's Republic of China and blood physiological knowledge, and the survey was conducted anonymously. The general characteristics of subjects, the cognition level of voluntary blood donation system and knowledge, the ways to acquire these knowledge, and the status and motivation of voluntary blood donation were analyzed. Results ①In this survey, we handed out 9 000 questionnaires, and 8 037 files were returned. Effective recovery ratio was 89.30%. 4 233 (52.67%, 4 233/8 037) of the participants were male, and 3 804 of them were female (47.33%, 3 804/8 037). The age range was from 16 to 65, and mean age was 32.65±12.55. Occupation of participants included civil servant, student, educator, peasant, soldier, and others. 63.35% (5 092/8 037) of participants had undergraduate degree. ② 90.89% of participants knew the voluntary blood donation system of China, but they were not entirely mastered the voluntary blood donation knowledge. The cognition levels of blood donation were different among different age participants (χ2=17.52, P<0.01), participants over 40 years old had a higher cognition level. participants with different levels of education had different levels of cognitive understanding of voluntary blood donation (χ2=76.85, P<0.01), participants with master degree had a higher cognition level; people with experience of blood donation had a higher cognition level (χ2=31.42, P<0.01). ③ Blood donation knowledge was achieved through watching TV (44.96%, 3 613/8 037), publicity in university or (39.02%, 3 136/8 037), publicity in donation cites (33.31%, 2 677/8 037), the internet (27.09%, 2 177/8 037), broadcasting (26.84%, 2 157/8 037), et al. And the behaviors of blood donation were different among participants who received blood donation knowledge through TV. The way from which participants received blood donation knowledge were different among those who did not donate blood (χ2=45.26, P<0.01). ④The top three motivations for voluntary blood donation were helping others (3 043/3 224, 94.38%), good for health (2 000/3 224, 62.03%), and group blood donation organized by university or company (1 227/3 224, 38.06%). Conclusions Blood collection and supply institutions should strengthen the promotion and education of voluntary blood donation to increase the blood donation rate of local citizens. Key words: Blood donor; Knowledge; Motivation; Questionaires