We report here the results of external quality assessment of blood bank tests performed in 2007. Survey specimens were sent three times to 448, 450, and 455 participant institutes, and the response rates were 99.3%, 97.3%, and 98.0%, respectively. Test items for the surveys were ABO grouping, Rh(D) typing, crossmatching, direct antiglobulin test, antibody screening and identification test. The average accuracy rates of ABO grouping and Rh typing were in the range of 99.5-100% and 98.9-100%, respectively. In crossmatching test, the accuracy rates were 96.0-97.1% for the compatible samples, 89.6-92.4% for the incompatible samples, and 89.6-92.4% for the samples which could be detected as incompatible only by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.0-99.7% for negative samples and 96.3-99.0% for positive samples. The correct results were reported by 95.7-100% of the surveyed institutions for antibody screening test and 98.2-100% for identification test. Fifteen institutions gave repeatedly incorrect answers for crossmatching. Five institutions out of them gave incorrect answers for all the test specimens sent out 3 times last year.