The invention belongs to the technical field of soil improvement and particularly relates to a fertilization pollution control type soil conditioner and a preparation method thereof. The first purpose of the invention is to provide the fertilization pollution control type soil conditioner. The conditioner comprises the following components: urea methanol, monopotassium phosphate and a heavy metal adsorption material. In view of the deficiencies of a conventional repair material, the second purpose of the invention is to provide the preparation method for the fertilization pollution control type soil conditioner. According to the soil conditioner and the preparation method, fertilizers required for crop growth can be provided and cannot be absorbed by plants due to passivation of heavy metal around crops in the fertilizer absorption process of the crops, thereby achieving the purpose of directional regulation and control; and the soil conditioner is low in cost and simple in formula, can improve the soil fertility on one hand and increase the pH value of soil, and has a remarkable passivation effect for heavy metal pollutants.