Based on the historical meteorological data of eight typical stations in Heilongjiang Province in recent 60 years (1956-2015), the crop water requirement (ETC) and the irrigation water requirement of rice in Heilongjiang Province during the whole growth period under floods and controlled irrigation were investigated using the Penman-Monteith formula and water balance model. The response of ETC and the irrigation water requirement to climate change was analyzed by combining with the characteristics of meteorological factors taking advantage of the Mann-Kendall Analysis. The results indicated that, the variation tendency of ETC in the same station under different irrigation modes were basically consistent. Specifically, the ETC of Anda and Suihua stations decreased significantly, which stands for the phenomenon known as ‘evaporation paradox’; however, that of Nenjiang, Shangzhi and Sunwu showed an opposite trend and the rest stations had no obvious variation. On the other hand, the irrigation water requirement of Shangzhi significantly increased both under the two irrigation modes, but in Sunwu, Fujin and Nenjiang, it increased only under controlled irrigation, and others showed no regularity. In conclusion, compared with flooding irrigation, the effective rainfall in controlled irrigation mode increased by 20% and the irrigation water requirement were reduced by 44.9%~52.9%, which effectively reduced the adverse effects of climate change on agricultural production.