Abstract: Objective To investigate the knowledge,attitude and practice on blood donation without compensation among population in Nanjing,and to provide scientific evidence for increasing blood-donators and improving the work of blood donation.Methods A questionnaire survey was conducted among 698 blood donators without compensation enrolled by random sampling.Results 54.2% of 698 blood donators participated the donation for the first time,and the proportion of donation in students was higher than in non-students.The correct proportion about the blood donation-related knowledge was 54.6%.As for intent of blood donation,92.1% of participants liked to donate blood,61.6% planed to do an emergency blood donation,30.3% liked to donate marrow.Conclusion The survey suggested that the propaganda about blood donation knowledge among general population should be developed and extended to increase blood donors and assure the safety of clinical blood use.