Automatic machine for the external cleaning of histology cassettes embedded in paraffin, comprising: - a first conveyor belt or tray for inserting histology cassettes in an unordered manner; - a second conveyor belt for inserting histology cassettes put in order onto guides; - a first viewing system that is configured to: - define the position and orientation of the histology cassette inserted in the automatic machine by the first conveyor belt or tray or by the second conveyor belt; and - detect the perimeter image and therefore knows the dimensions of the cassettes; - a cleaning station where one or more tools are arranged, the one or more tools capable of removing the residual paraffin present on each outer side of the cassette; - a handling system or robot configurated to receive from the viewing system the coordinates for moving and rotating to pick up the cassettes according to its position; - a clamp located on the handling system or robot by means of an interface plate and provided with four heatable grippers, wherein the grippers are heatable by means of micro-resistances applied on the grippers and wherein the clamp is actuable by means of an actuator and a pusher which in turn acts on levers; - a drawer for the residues resulting from the cleaning of the histology cassette; - one or more horizontal or vertical outlet trays or slides of the clean histology cassettes; - a second viewing system 1D-2D capable of: - reading the identification code placed on the inclined side of the clean histology cassettes exiting the machine; and - putting in order and dividing said clean cassettes on the one or more horizontal or vertical outlet trays or slides. - a first conveyor belt or tray for inserting histology cassettes in an unordered manner; - a second conveyor belt for inserting histology cassettes put in order onto guides; - a first viewing system that is configured to: - define the position and orientation of the histology cassette inserted in the automatic machine by the first conveyor belt or tray or by the second conveyor belt; and - detect the perimeter image and therefore knows the dimensions of the cassettes; - define the position and orientation of the histology cassette inserted in the automatic machine by the first conveyor belt or tray or by the second conveyor belt; and - detect the perimeter image and therefore knows the dimensions of the cassettes; - a cleaning station where one or more tools are arranged, the one or more tools capable of removing the residual paraffin present on each outer side of the cassette; - a handling system or robot configurated to receive from the viewing system the coordinates for moving and rotating to pick up the cassettes according to its position; - a clamp located on the handling system or robot by means of an interface plate and provided with four heatable grippers, wherein the grippers are heatable by means of micro-resistances applied on the grippers and wherein the clamp is actuable by means of an actuator and a pusher which in turn acts on levers; - a drawer for the residues resulting from the cleaning of the histology cassette; - one or more horizontal or vertical outlet trays or slides of the clean histology cassettes; - a second viewing system 1D-2D capable of: - reading the identification code placed on the inclined side of the clean histology cassettes exiting the machine; and - putting in order and dividing said clean cassettes on the one or more horizontal or vertical outlet trays or slides. - reading the identification code placed on the inclined side of the clean histology cassettes exiting the machine; and - putting in order and dividing said clean cassettes on the one or more horizontal or vertical outlet trays or slides.