Abstract: Objective To analyze the distribution pattern and changing trend on gender,age and background（organizations or individuals）among voluntary blood donors from 2011 to 2015,evolve and improve reference basis for donor recruitment measures.Methods Collected data of blood donors in Dalian from 2011 to 2015 including gender,age and background（organizations or individuals）.Then analyzed the distribution varied trend of donators employing Tangshan Qiao Analyzing System．Results The number of blood donors in Dalian has been increasing every year.Male blood donors always exceed females in scale.The gender gap has further widened beyond proportion（63.2%VS36.8%）and the difference was statistically significant （P<0.01）; the mean age of blood donors has increased by 2.5 years（P<0.01）.From 2011 to 2015,the donation proportion of aged 18~25 decreased gradually（49.2%VS38.7%,P<0.01）,and no significant differences was observed in the age group of >25~35 （26.1%VS25.9%,P>0.05）,but>35~45 and over>45 gradually increased（17.2%VS21.6%,P<0.01;7.5%VS13.8%,P<0.01）．From 2011 to 2015,the ratio of individual blood donation decreased from 82.4% to 72.8%（P<0.01）while that of organization donors increased from 17.6% to 27.2%（P<0.01）.Conclusion The distribution of voluntary blood donors in Dalian,including gender,age and background（organizations or individuals）,has its own characteristics．The donation proportion of voluntary blood donors from different population shows great volatility,so we should strengthen publicity toward blood donors from different age and education levels,establish reasonable blood donor recruitment measures and ensure enough blood supply．

Key words: Blood donors, Gender, Age, Individual blood donation, Organization blood donation