The invention provides a method for quantifying influence on basin water resources by climate change and human activities. The method comprises the following steps: S1, dividing a long sequence reference period; S2, carrying out restore calculation on hydrologic features of rainfall and temperature; S3, establishing a foundation database; S4, carrying out large-scale basin distributed hydrologic simulation; S5, quantitatively representing influence sub-items of the climate change and the human activities. According to the method provided by the invention, a basin distributed hydrologic model, a hydrologic feature restore technology and a sub-item quantifying method are effectively coupled, the method for quantifying the influence on the basin water resources by the climate change and the human activities is established, and the method has important significance to decisions such as basin water resource evolution analysis and identification, water source project planning layout and water resource space allocation in a varying environment.