A natural leather trimming machine (P) comprising: - an ironing device for stretching and removing creases and wrinkles of said natural leather (P); - cutting means arranged downstream of said ironing device , and configured to cut said natural leather (P) along at least one cutting line (L); - a detection unit arranged in correspondence of the entrance of said natural leather (P) into said cutting means , said detection unit being configured to detect the position of said natural leather (P), the conformation of at least one end edge (B) thereof, and the position of any defects (D) of said natural leather (P) in proximity to said at least one end edge (B); - a plurality of conveyor belts configured, respectively, to move said natural leather (P) from said ironing device towards said detection unit , present and subsequently move said natural leather (P) away to/from said cutting means; - a first command and control unit configured to determine the cutting coordinates of the natural leather (P) on the basis of said position of said natural leather (P), of said shape of at least one end edge (B), and of said position of any defects (D), wherein said cutting coordinates define said at least one cutting line (L); said machine being characterised in that said cutting means comprise at least one laser source , and said conveyor belt of said plurality of belts has a conveying surface made with a metal mesh to prevent the laser emitted by said at least one source rebounding on said natural leather (P); said machine also comprising a shielding container inside of which is positioned said at least one laser source . - an ironing device for stretching and removing creases and wrinkles of said natural leather (P); - cutting means arranged downstream of said ironing device , and configured to cut said natural leather (P) along at least one cutting line (L); - a detection unit arranged in correspondence of the entrance of said natural leather (P) into said cutting means , said detection unit being configured to detect the position of said natural leather (P), the conformation of at least one end edge (B) thereof, and the position of any defects (D) of said natural leather (P) in proximity to said at least one end edge (B); - a plurality of conveyor belts configured, respectively, to move said natural leather (P) from said ironing device towards said detection unit , present and subsequently move said natural leather (P) away to/from said cutting means; - a first command and control unit configured to determine the cutting coordinates of the natural leather (P) on the basis of said position of said natural leather (P), of said shape of at least one end edge (B), and of said position of any defects (D), wherein said cutting coordinates define said at least one cutting line (L); said machine being characterised in that said cutting means comprise at least one laser source , and said conveyor belt of said plurality of belts has a conveying surface made with a metal mesh to prevent the laser emitted by said at least one source rebounding on said natural leather (P); said machine also comprising a shielding container inside of which is positioned said at least one laser source . <EOS>