Surveys for external quality assessment in blood banking were carried out in 1997. The response rate was 62.9% for 1st trial, 68.8% for 2nd trial and 88.0% for 3rd trial. Test items were ABO cell and serum groupings, Rho(D) typing, cross-matching, direct antiglobulin-test, antibody screening and identification test. The average accuracy rates of ABO cell and serum grouping were more than 99.0% and 99.4% respectively. The accuracy rates of Rho(D) typing were 100% for positive samples and 99.0% for negative ones. The average accuracy rates of cross-matching were 97.0% for compatible samples, 99.2% for Incompatible samples which could be detected by saline method, and 84.8% for incompatible samples which could be detected only by 37℃ albumin and 59.3% by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.6 for negative samples and 86.0% for positive samples. The accuracy rates of antibody screening test were 97.0% and those of antibody identification were 95.0%.