A method for recovering plastic from complex materials; comprising, at least, the following phases: a) a first grinding of the complex product into granules of 8 to 12 millimetres in a mill with aspiration; b) a first grouping into balls of the polyester fluff contained in the product obtained from the first grinding, in a drum with aspiration, c) a first separation of the polyester balls and the remaining mixture of plastic with polyester in a first sifter with aspiration; d) a second grinding of the remaining mixture into granules of 4 to 6 millimetres in a mill with aspiration; e) accumulating and dosing the product from the second grinding by means of a metering hopper with aspiration; f) a second grouping into balls, in a drum with aspiration, of the polyester fluff contained in the product obtained from the second grinding; g) a second separation of the polyester balls and the remaining mixture of plastic with polyester in a second sifter with aspiration; h) a third grinding of the remaining mixture into granules of a size equal to or smaller than 2 millimetres, in a mill with aspiration; i) a third grouping into balls of the polyester fluff contained in the product obtained from the third grinding in a drum with aspiration, j) a separation by aspiration of the suspended dust contained in the product obtained from the third grinding in a hopper; k) a third separation of the polyester balls and the remaining mixture of plastic with polyester in a third sifter with aspiration; l) removing the polyester fluff contained in the remaining mixture of plastic with polyester from the third separation by successive agitation of said remaining mixture and respective removal of the polyester fluff by sifting, aspiration, blowing and/or propulsion, until a plastic purity of 99.99% is obtained. a) a first grinding of the complex product into granules of 8 to 12 millimetres in a mill with aspiration; b) a first grouping into balls of the polyester fluff contained in the product obtained from the first grinding, in a drum with aspiration, c) a first separation of the polyester balls and the remaining mixture of plastic with polyester in a first sifter with aspiration; d) a second grinding of the remaining mixture into granules of 4 to 6 millimetres in a mill with aspiration; e) accumulating and dosing the product from the second grinding by means of a metering hopper with aspiration; f) a second grouping into balls, in a drum with aspiration, of the polyester fluff contained in the product obtained from the second grinding; g) a second separation of the polyester balls and the remaining mixture of plastic with polyester in a second sifter with aspiration; h) a third grinding of the remaining mixture into granules of a size equal to or smaller than 2 millimetres, in a mill with aspiration; i) a third grouping into balls of the polyester fluff contained in the product obtained from the third grinding in a drum with aspiration, j) a separation by aspiration of the suspended dust contained in the product obtained from the third grinding in a hopper; k) a third separation of the polyester balls and the remaining mixture of plastic with polyester in a third sifter with aspiration; l) removing the polyester fluff contained in the remaining mixture of plastic with polyester from the third separation by successive agitation of said remaining mixture and respective removal of the polyester fluff by sifting, aspiration, blowing and/or propulsion, until a plastic purity of 99.99% is obtained.