In order to overcome the narrow glass-forming compositional range with traditional melt-quenching method, we here performed the mechanical milling and Spark Plasma Sintering technology to fabricate a high Ge content chalcogenide glass, the Ge40As40Se20 glass, which locates edge of the Ge-As-Se glass-forming domain. By using the optimal ball milling time of 50 h and sintering stress of 37.5 MPa, the large size Ge40As40Se20 bulk glasses were obtained, which possesses both a large Vickers hardness of 369 kgf/mm2 and a relative high infrared optical transmission of 43 % (@5 and 9 μm). Moreover, it was found there are pores in the sintered glasses more or less, and the pore size and number significantly affect the transmission, i.e., the optimal Ge40As40Se20 bulk glasses were demonstrated has the smallest and least pores via scanning electron microscope. The combination of mechanical milling and low-temperature sintering methods has been confirmed can be used to improve the glass formability and then obtain the high Ge content component with a potential high hardness glass to break through the limited mechanical property of chalcogenides.