The invention relates to a hybrid material water solution loading metal nanoparticles, and a preparation method thereof. The hybrid material water solution is a solution formed by dissolving a hybrid material in water. The hybrid material is composed of carrier molecules A, stabilizing agent molecules B and metal nanoparticles. The method comprises the following steps: a water solution of A and a water solution of B are mixed by stirring; the pH of the mixed solution is regulated; a metal ionic salt solution and a reducing agent solution are sequentially dropped into the mixed solution; and stirring is carried out, such that the hybrid material water solution is obtained. In the hybrid material, the metal nanoparticles are stably and effectively connected to the molecular chain of carrier molecules in forms of ion bonds and coordination bonds, such that the hybrid material has the advantages of good solubility and adjustable metal nanoparticle loading amount. The preparation method of the hybrid material water solution has the advantages of no pollution, less product impurity and simple operation. The prepared hybrid material solution loading metal nanoparticles can be widely applied in the aspects of antibacterial finishing solutions, self-assembly stock solutions, catalysis materials and the like.