The antibody screening of 26,527 blood donors at Songklanagarind Hospital was analyzed. The saline technique found 265 samples were positive, accounting for identification of irregular antibodies in the positive sample was studied by panel cell. Anti-Le^a, anti-Le^b, anti-Le^a+b, anti-Mia, anti-P₁, anti-E and anti-c were detected in 111, 55, 72, 4, 13, 2 and 1 samples respectively. Confirmation of the results was obtained by red cell typing, which used an in-house antibody prepared from donated plasma with a known antibody. The known antibody plasma was stock in aliqouts at -20 ^oC for red cell typing. Antibody identification in donated blood is very useful for patients. The in-house antibody reduced the hospital cost because commercial antibodies are very expensive, about 1,000 baht/ml.