Belonging to the field of environmental protection building materials, the invention discloses a preparation method of a cement-sand composite water permeable brick. The method comprises: first mixing cement, gravel and additives evenly, putting the mixture into a mold so as to prepare large aperture water permeable brick core, mixing water glass with sand to obtain wrapped water glass sand, mixing the dried brick core with the wrapped water glass sand, wrapping the brick core, carrying out flatting molding and complete maintenance, then spraying a layer of resin uniformly on the surface, leaving the resin to dry completely, thus obtaining the cement-sand composite water permeable brick. The cement-sand composite water permeable brick provided in the invention combines the advantages of common water permeable bricks and sand-based permeable bricks. By employing a cement-sand composite technology, the preparation process is simple, and by utilizing inexpensive raw materials, the economical, practical, green and environment-friendly cement-sand composite water permeable brick can be prepared, and has the strength properties lacked by ordinary water permeable bricks. Thus, the purpose of sand control is achieved, and the problem of the high cost of water permeable bricks is also solved.