Background: In spite of, extensive efforts and a number of blood donation programs being organized worldwide, availability of adequate and safe blood still remains short to meet the increased demand in developing countries including Ethiopian. The major challenge was recruitment of voluntary, non-remunerated blood donors. Literatures identified that many factors are responsible such as, lack of knowledge, negative attitudes, and inconvenience for facilities. Increase level of knowledge and positive attitude towards voluntary blood donation in young people is highest priority. Methods: Institutional based cross-sectional quantitative study was used to assess KAP and associated factors towards voluntary blood donation (VBD) among health science students of Samara University, Afar Northeast Ethiopia, using pre-tested structured self-administered questionnaire. Stratified sampling method was used and individual was selected by simple random sampling method. Data was analyzed by SPSS version 20.0. Logistic regression analysis was used to identify associated factors. Predictor variables with p-values up to 0.25 in bivariate regression were entered to multivariate regression and p-value