The invention belongs to the technical field of copper-clad plate production, and especially relates to a preparation method of a halogen-free CEM-1 copper-clad plate with a high peeling strength. Phosphor containing epoxy resin and bisphenol A type epoxy resin are taken as the main resin; phosphor containing linear phenolic resin is taken as the curing agent, polyfunctional epoxy resin is used to enhance the heatproof performance; a certain ratio of aluminum hydroxide is added to increase the electric tracking resistant index of the copper-clad plate; a nitrogen and phosphor containing fire retardant is added, and through the synergistic effect between nitrogen and phosphor, the fireproof performance of the copper-clad plate is enhanced and can reach the FV0 grade. By processing the surface of used filling material and controlling the particle size, the filling material can be evenly dispersed into resin glue to obtain uniform glue dipped sheets, the toughness of sheets is improved, the obtained copper-clad plate can reach the environment protection requirements and does not contain any halogen, the contents of chlorine and bromine are low, the peeling strength is high, the characteristic of resisting tracking caused by electric leakage is excellent, and CTI>=600V.