Provided is a method for measuring the flow vector of seepage liquid. The method includes the following steps that 1, rock is selected; 2, observation points are selected; 3, pigment is arranged on the observation points; 4, a transparent opposite face model of a rock fracture face is made; 5, the transparent opposite face model is arranged on the rock fracture face; 6, transparent sulfuric acid grid paper is placed on the upper surface of the transparent opposite face model; 7, a camera device is installed; 8, water injection is performed till seepage occurs; 9, multiple flow path lines with colors appear; 10, flow conditions are recorded; 11, a shot image is analyzed, the seepage speed of any point at the minimum time difference is calculated, and then the seepage vector of any point of the fracture face at any micro time period is measured. By means of the method for measuring the flow vector of the seepage liquid, the problem that it is impossible to trace the seepage direction of any point and calculate the seepage speed can be solved, the instant flow speed of liquid at any point in a fracture joint face can be measured, and measurement precision is high.