A genetic study was carried out on phenotype and gene frequencies of the genetic markers in eight red cell enzymes: glyoxalase I (GLO1), glutamic pyruvate transaminase (GPT), phosphoglucomutase (PGM1), esterase D (ESD), adenylate kinase (AK1), 6-phosphogluconate dehydrogenase (6-PGD), adenosine deaminase (ADA), acid phosphatase (ACP1), in the Hungarian ethnic group living in Yugoslavia. The gene frequencies obtained were: GPT*1 = 0.542, PGM1*1 = 0.760, ESD*1 = 0.909, AK*1 = 0.971, PGD*A = 0.971, ADA*1 = 0.939, GLO1*1 = 0.417, ACP1*A = 0.329, ACP1*B = 0.591 and ACP1*C = 0.080. The distribution of these phenotype and gene frequencies was examined and compared with the phenotype and gene frequencies found for the Hungarian population living in Hungary and for other populations living in the northeast of Yugoslavia.