The invention relates to a method for testing starting pressure of a water injection well and belongs to the technical field of petroleum exploration and development testing processes. According to the method for testing starting pressure of the water injection well, a water distribution string is used for dividing the water injection well into N water injection layers, the corresponding relation between starting flows and stopping flows of water injection layer segments corresponding to different flow levels is established, and pressure corresponding to the starting flow of each water injection layer is determined. The method has the beneficial effects as follows: the problem of large errors of recorded starting pressure data of the water injection layers of the water injection well in different flow levels under the condition of real oil reservoir is solved, pressure and flow level differences of the water injection layer segments of the water injection well are finely divided, the starting pressure data is recorded rapidly, the data is accurate, detailed and reliable, and technical support is provided for fine injection and recovery adjustment of oil-water wells in the oil field.