The invention discloses controlled release inhibitor coated urea and a preparation method and application thereof. In the present invention, a DCD-containing water-soluble inhibitor and an isocyanatecompound are used, and after coating materials are uniformly mixed by means of mechanical adsorption, ultrasonic vibration and molecular adsorption, large-particle urea is packaged in one step by in-situ reaction cross-filming. The traditional process for producing inhibitor-type fertilizers is changed, and the controlled-release inhibitor coated urea fertilizer with simple operation, an easy-to-adjust formula and low cost, and a preparation method of the urea fertilizer are developed. On the basis of ensuring the inhibitory effect, the problems of easy leaching and decomposition of the inhibitor materials are solved, and the technical bottlenecks of high usage amount of an existing similar coating material and short nutrient release period of a fertilizer are overcome, and the controlledrelease fertilizer can show multiple times of nutrient release peak curve characteristics.