Pasture irrigation has been much paid attention to for the increase of forage yield and persistence in dry area. This field experiment was conducted to determine the effects of irrigation and nitrogen(N) fertilization on the soil moisture retention, regrowth and yield of orchardgrass/ladino clover mixtures during the dry season. Irrigation point was 0.5bar, irrigation method was sprinkler system, and N levels (subplot) were 140, 280 and 420 ㎏/㏊. The experiment was performed at Livestock Experiment Station in Suweon, 1985. The results are summarized as follows: 1. Considering the meteorological conditions during the experimental period, the temperature was higher by 0-2℃ than that of average year, and the dry season was prolonged from May 20 to June 26. 2. With irrigation the temperature of soil surface and underground was decreased by 4.4℃ and 1.6℃, respectively. 3. The regrowth plant length, leaf area and dry weight of grasses with irrigation were markedly increased during the dry season. Also under the irrigation condition the regrowth speed was significantly increased with increasing level of N, while that of unirrigated pasture was no differences between the plots of N 280 and N 420 ㎏/㏊. 4. With irrigation dry matter yield (5.9 t/㏊) and fresh yield (35.4 t/㏊) during the dry season (at the second and the third cut) were significantly (P$lt;0.05) increased by 36% and 50%, respectively. 5. Yield of irrigated pasture was rapidly (P$lt;0.05) increased with increasing level of N application. However, that of unirrigated pasture was shown no difference between the plots of N 280 and N 420 ㎏/㏊.