Abstract: As the “ballast stone” of China’s food security, heilongjiang province’s rational and effective use of water resources provides an important guarantee for food production.Based on the water footprint theory, this paper calculated the water footprint and gray water footprint of grain production in 14 regions of heilongjiang province from 2000 to 2017 as input and output indicators, and used the three-stage super-efficiency SBM-Malmquist model to analyze the spatial and temporal characteristics of the green water efficiency of grain production in heilongjiang province.The results showed that the total water footprint of grain production in heilongjiang province increased first and then decreased, with great differences among different regions, which were mainly caused by the changes of grain yield, planting structure and yield per unit area.Affected by the demand of fertilizer for grain production and the policy of zero growth of fertilizer, the total footprint of grainy water increased first and then decreased.After removing the random error and environmental factors, the external factors have a significant effect on the pure technical efficiency.The green efficiency of water used for grain production in heilongjiang showed a trend from rising to stable. Except for Harbin and the general administration of agricultural reclamation, the efficiency among different regions was low.The change of green total factor productivity (TFP) of water used in grain production mainly depends on the change of technological progress and is limited by the change of pure technological efficiency.It is suggested that heilongjiang province should further develop modern agriculture, expand production scale according to regional characteristics, increase scientific and technological input and technological innovation, optimize and adjust the input and output factors in the production process from the perspective of grain production structure and fertilizer application amount, which is an important way to improve the green efficiency of water use in grain production.