Abstract: 20 Duluoke（paternal） Hybirdpigs were used to investigate the polymorphism of plasma cerumLoplasmin（Cp）by means of a polyacrylamide gel eletrophoresis in vertical plate.The results were as follows： ①There were both CpAB and CpBB phenotypes on the locus of plasma cerumLoplasmin in Duluoke binary and ternary Hybirdpigs examined and CpBB type was a preponderance phenotypes； ②The frequencies of CpA and CpB alleles were 0.1429,0.2308 and 0.8571,0.7692 in Duluoke binary and ternary Hybirdpigs examined; ③The gene heterozygosities were separate 0.2441,0.3350，the gene homozygosities were separate 0.7559,0.6650，the numbers of effective allele were separate 1.3229,1.5038 and the gene homozygosity indexes were separate 0.7152,0.6371. 

Key words: Duluoke; binary hybrid-pig; ternary hybrid-pig; plasma cerum loplasmin; polymorphism