This study was carried out to obtain basic data for breeding plan in swine. Genetic parameters for economic traits of swine were estimated on the basis of the data from 6,948 pigs of Duroc, Landrace and Large White tested at a swine farm in Young Kwang County, Junnam Province from 1991 to 1997. The heritabilities of average daily gain, age at 90㎏, backfat thickness, body length and body height were 0.26, 0.37, 0.53, 0.40 and 0.40, respectively. The heritabilities of average daily gain in Duroc, Landrace and Large White were 0.29, 0.30 and 0.17, respectively. Those of age at 90㎏ in Duroc, Landrace and Large White were 0.45, 0.43 and 0.25, respectively. The backfat thickness heritabilities in the three breeds were 0.28, 0.53 and 0.54, respectively. T`he heritabilities estimated for body length and body height were 0.17 and 0.39 in Duroc, 0.47 and 0.50 in Landrace, 0.47 and 0.29 in Large White, respectively. The genetic and phenotypic wrrelations of average daily gain with age at 90㎏, estimated for Duroc, Landrace and Large White were -0.313 and -0.759, -0.784 and -0.783, -0.725 and -0.783, respectively. Those of body length with body height were 0.178 and 0.262, 0.514 and 0.294, 0.324 and 0.344, respectively. The correlations of breeding and phenotypic values in Duroc, Landrace and Large White were 0.593, 0.561 and 0.493 in average daily gain, 0.711, 0.730 and 0.552 in age at 90㎏, 0.708, 0.654 and 0.715 in backfat thickness, 0.558, 0.286 and 0.690 in body length, 0.716, 0.328 and 0.702 in body height, respectively.