This study was undertaken to estimate genetic gains for ME 305-day milk and fat yields using a total 54,839 milking records of 26,635 cows with first parity record calved from 1985 to 1996. The correlations of sire`s breeding values for milk and fat yields between 1, 1∼2 and 1∼3 parity datasets with 1-6 parity dataset were 0.615, 0.794, 0.975 and 0.565, 0.850, 0.980, respectively. The genetic gains per year for milk and fat yields were increased markedly with increasing parity records of cows.