To investigate the genetic polymorphisms and constitutions of blood proteins and enzymes in the Korean native cattle population of National Livestock Cooperatives Federation(NLCF), the genetic variants of transferrin(Tf), post-transferrin-2(pTf-2), albumin(Alb), post-albumin(pAlb), ceruloplasmin(Cp), amylase-I(Am-I) and herroglobin(Hb) were analyzed using the PAGE(polyacrylamide gel electrophoresis) and ST AGE(starch gel electrophoresis) methods. On the genetic variants of the serum proteins, the transferrin(Tf) locus was assumed to be genetically controlled by codominant alleles, Tf A, $D_1$, $D_2$ and E alleles, and the gene frequencies of these were 0.249, 0.248, 0.260 and 0.243, respectively. The post-transferrin locus was observed to be controlled by pTf-2 F and S alleles, and the gene frequencies of these were 0.662 and 0.338, respectively. The post-albumin(pAlb) loci were identified to be controlled by two alleles, pAlb F and S alleles for pAlb locus, and the gene frequncies of these were 0.440 and 0.560 for pAlb F and S alleles, respectively. On the genetic variants of the serum enzymes, ceruloplasmin(Cp) and amylase-I(Am-I) loci were found to be controlled by two alleles, Cp F and S for Cp locus, and Am-I B and C for Am-I locus, and gene frequencies of these were 0.319 and 0.681 for Cp F and S, and 0.871 and 0.120 for Am-I Band C, respectively. On the genetic variants of the hemoglobin(Hb), the distributions of genotypes were 76.5, 21.2 and 2.3% for Hb AA, AB and BB types, and the gene frequnecies for Hb A and B were 0.871 and 0.129, respectively. On the effects of genetic variants of blood proteins, Tf $D_1D_1$, $D_2D_2$ and $D_2E$ genotypes were significantly higher on body weight at 6 month and average daily gain than that of other Tf genotypes.