The invention provides an application and a preparation method of a ZSM-5 molecular sieve with mesopores and micropores. The preparation method includes steps of precursor preparation, silica-alumina gel preparation and preparation of the ZSM-5 molecular sieve with the mesopores and micropores.In a preparation process of a hierarchical porous catalyst, consumption of a microporous templating agent and a mesoporous templating agent can be substantially reduced, synthesis steps of the hierarchical porous catalyst are simple, and the synthesized molecular sieve is large in specific surface area, uniform in particle size and controllable in mesopore quantity and size, and intrinsic lipophilicity of the molecular sieve is enhanced due to abundant surface terminal hydroxide radicals. By adoption of the molecular sieve as the catalyst, a method for preparing cyclohexanol by direct hydration of cyclohexene is established, and the catalyst is high in cyclohexene conversion rate and cyclohexanol selectivity.