The invention discloses a method for producing an acrylic plate by acrylic wastes and belongs to the technical field of organic glass. The method comprises: S1, cleaning, drying and crushing acrylic wastes, mixing the wastes and magnesium oxide powder and carrying out cracking, S2, salting out, distilling and alkalizing a crude monomer to obtain a monomer refined product, S3, mixing the monomer refined product, an initiator and dibutyl phthalate and carrying out pre-polymerization, S4, adding a flame retardant, wood chips, an ethylene-vinyl acetate copolymer resin, a coloring agent and an ultraviolet absorber into the prepolymer and carrying out stirring to obtain mixed slurry, S5, cooling the mixed slurry, carrying out vacuum defoaming and pouring the slurry into a mold, and S6, feeding the mold into a hot water tank, carrying out heating polymerization and carrying out cooling and demolding. The method realizes recovery and recycling of acrylic wastes, saves a cost and is environmentally friendly and economical. The produced acrylic plate has high integrated quality, market competitiveness and high practicability.