In order to quantitatively analyze the impact of land use changes on runoff in the Minjiang River basin, combined with the scenario setting method, SWAT model was constructed to simulate the runoff process under different land use scenarios in this study. The results showed that: (1) The parameterized SWAT model had good applicability to runoff simulation in the Minjiang River Basin with the evaluation indexes R²>0.9,NSE>0.8,|PBIAS|<10% at calibration and validation periods. (2) When the current land use was set as the reference, the annual runoff increased by 12.41%, 22.89% for the farmland reserve scenario and construction development scenario respectively, and decreased by 4.09%, 1.61% under the vegetation restoration scenario and zoning scenario, indicating that the forestland and grassland had the stronger mitigation effect on the runoff and reduced the inter annual variation of runoff, while farmland and construction land increased the runoff. (3) Combined with the value of conservation index and the simulation results of monthly average runoff in wet reason and dry periods, it was studied that the forestland and grassland had the stronger capacity of reserving water and regulating runoff, while that of farmland and construction land was weak, but the former was better than the latter. (4) Based on the "reasonable development of farmland and protection of forest in the north of West Fujian, and the promotion of ‘slope industry’ in the north of East Fujian", the zoning scenario could not only effectively decrease and regulate the runoff of the Minjiang River basin, but also ensure the grain safety and economic development, realize the unity of ecological and economic benefits, and provide reference for the scientific, efficient and sustainable land use planning of the basin.