Optimizing and maximally utilizing water resources are key issues of water resource management. The agriculture- to- urban water transfer has diverse features in different spatial and temporal scales, and the effect of influencing factors changes variously on different scales. In this study, nine factors influencing agriculture- to- urban water utilization are chosen, and their degrees of influence are analyzed by using ridge regression based on provincial panel data from 2003 to 2010. The result shows that the degree and direction of each factors influencing on the agriculture-to-urban transfer are not entirely consistent at different spatial and temporal scales. From the aspect of time scale, the industrial structure transformation and the degree of urbanization are always the main factors, and the comprehensive impact is 0.53. As time goes on, the effects of different factors show great diversity. From the aspect of space scale, the industrial restructuring and the level of urbanization have significant positive impacts on the national scale, which are 0.32 and 0.21 respectively. In highly water shortage areas, the factors having extremely positive impacts include the industrial structure transformation, eco-environment improvement, irrigation saving rate and per capita water resources. In serious water shortage areas, the positive effects of factors are not very different. In medium water deficient areas, the industrial structure transformation is the major driver, and its impact is 0.56. The minor water deficient areas are influenced mainly by industrial structure transformation, urbanization, effective irrigation rate, population and irrigation saving rate. The key factors in the water resources abundant regions are GDP, urbanization and water using comparative income. From the temporal and spatial scales, the change of comparison income of utilization in water resources is a major constraint factor. It is not completely same of each factor's driving directions to water transfers in different areas and times.