The invention provides a cooling structure device for grinding a straight surface of a tenon tooth blade and root intermediate, and can solve the problem of burning during grinding on the straight surface of the tenon tooth blade and root intermediate. The cooling structure device for grinding the straight surface of the tenon tooth blade and root intermediate comprises an intermediate positioningblock of an existing grinding clamp, wherein the intermediate positioning block comprises a positioning base and a cover plate which are obtained by cutting the intermediate positioning block from the middle of the top surface of the intermediate positioning block; a horizontal through hole is formed in the middle of the positioning base in the length direction of the positioning base; a plurality of vertical through holes which communicate with the horizontal through hole vertically are formed in the positioning base in the length direction of the positioning base and are positioned above the horizontal through hole; first injection openings which face the vertical through holes one by one are formed in the edge of the top surface of the positioning base and are positioned on the outer side of the cover plate; each first injection opening communicates with the corresponding vertical through hole obliquely; blind holes which face the vertical through holes one by one are formed in thebottom surface of the cover plate; the diameters of the blind holes are greater than the diameters of the vertical through holes; second injection openings which face the blind holes one by one are formed in the edge of the top surface of the cover plate; and each second injection opening communicates with the middle of the corresponding blind hole obliquely.