The invention provides a rack structure of a digital printing machine. The structure comprises a printing operating console, a plurality of bottom fulcrum bars, a plurality of bases, a heat insulating protective plate, a heat-conducting plate, a printing plate, a pressing plate, a supporting stand column, a hydraulic telescoping cylinder, a pair of hydraulic telescoping columns, a pair of connecting plates, and a pair of lifting yokes. The plurality of bottom fulcrum bars are connected with the printing operating console and the bases. The heat insulating protective plate is arranged on the upper end face of the printing operating console. The heat-conducting plate is embedded in a concave surface of the heat insulating protective plate in an adaptive manner. The pressing plate is embedded in a concave surface of the printing plate in an adaptive manner. The lower end of the supporting stand column is fixedly connected with the middle part of the rear end of the printing operating console. The hydraulic telescoping cylinder is arranged on the upper end of the supporting stand column. The hydraulic telescoping columns are connected with the hydraulic telescoping cylinder. The hydraulic telescoping column is connected with the printing plate through the connecting plate. The pair of connecting plates are respectively symmetrically arranged on two sides of the middle part of the printing plate. The pair of lifting yokes are respectively symmetrically arranged on two side edges of the printing plate. The rack structure of a digital printing machine is used for digital printing, and is uniform in hot pressing, and meanwhile heat can be effectively isolated, preventing a user from being scalded.