The invention relates to a machine for harvesting corn, peeling corn husks and separating straws. The machine comprises a vehicle body, a corn header, a corncob elevator, a stem conveying device, a straw, a husk and pulp separation device and a corn storage bunker, and is characterized by further comprising a corn husker, wherein the corncob elevator comprises a first corncob elevator and a second corncob elevator, the first corncob elevator is connected with a corncob picking header and the corn husker, and the second corncob elevator is connected with the corn husker and the corn storage bunker. The invention further relates to a working method of the machine for harvesting corn, peeling corn husks and separating straws. According to the machine for harvesting corn, peeling corn husks and separating straws, and the working method of the machine, an elevating mechanism of a corn harvester is improved, the corn husker is added, and a mounting structure of a traditional corn husker is improved, so that the harvested corn can be further processed after separated from the straws, then the harvested corn is put in storage, and the labor intensity during field operation in the corn picking period is greatly reduced.