Based on the grey system theory, the prediction model of water consumption in colleges and universities was established with five main factors affecting water consumption including number of people using water, land area, greening rate, water supply efficiency of pipe network and penetration rate of water-saving appliances, the grey correlation coefficient and correlation degree of each factor were calculated, and then the water consumption prediction model was used and analyzed. The prediction results show that excluding the influencing factors of vacation, the relative error between the predicted water consumption and the measured water consumption in other quarters is less than 5 %, and the posterior error ratio of the model is 0.089. The prediction results are basically consistent with the actual situation, and the prediction accuracy of the model meets the engineering standard.