The invention belongs to the technical field of bactericides. The invention relates to a prothioconazole intelligent microcapsule suspending agent and a preparation method thereof. The suspending agent comprises the following components in percentage by weight: 1-5% of polypropylene oxide, 1-3% of an emulsifier, 2-40% of prothioconazole, 2-8% of caprylic / capric triglyceride, 2-8% of isopropyl myristate, 1-5% of polyacrylic acid, 1-3% of a surfactant, 0.1-0.3% of xanthan gum, 3-5% of glycerin, 0.1-0.3% of Kathon, 0.5-2% of magnesium aluminum silicate, 1-2% of hydrochloric acid and the balance of water. The preparation method comprises the following steps: preparing an oil phase, preparing a water phase, emulsifying, adjusting a pH value, microencapsulating and preparing the suspending agent. The microcapsule suspending agent disclosed by the invention has self-assembly, self-repair and high pH sensitivity, and meanwhile, the lasting period can be prolonged by slow release, and the use frequency is reduced, so that the use amount of pesticides is reduced. The method is simple in process and capable of effectively achieving mass production, and therefore the method has a high application value.