The invention discloses a preparation method of a perovskite solar cell photoelectric conversion layer. The preparation method comprises the steps of preparation of a leaded perovskite material solution, preparation of a displacement solution and generation of a photoelectric conversion layer. According to the method, the leaded perovskite material solution is prepared firstly, and then lead in the solution is replaced by metal displacement powder so that the lead removing process is simple and practicable, the requirement for the reaction condition is low and the lead removing effect is great, and thus the preparation method is suitable for industrial production and convenient for popularization.