Marking pen used for accurately scribing during radiotherapy

The invention discloses a marking pen used for accurately scribing during radiotherapy. The marking pen comprises a pen cap, a pinhead-type pen point, an ink storage refill, a pen holder, a rubber cap, a cotton core canister, an alcohol storage cotton core and a cotton core cap, wherein the pinhead-type pen point is positioned at the front end of the pen holder; the ink storage refill is positioned in the penholder; the pinhead-type pen point is connected with the ink storage refill; the pen cap is buckled at the front part of the pen holder; the rubber cap is positioned at the rear end of the pen holder; the cotton core canister is fixed at the rubber cap; the alcohol storage cotton core is positioned in the cotton core canister; the cotton core cap is buckled at the cotton core canister; and the exposed part of the pinhead-type pen point has the length of 30mm and the diameter of 1mm. The marking pen used for accurately scribing during radiotherapy is convenient to carry, simple in structure and convenient in use, and can be used for marking the body position of a patient, accurately scribing and drawing points, accurately marking and improving the repositioning precision during radiotherapy; and marking liquid used in the marking pen has less possibility of dropping off and can be acquired conveniently; and the marking pen has the advantages of convenience in carrying, accurate marking, simple structure, convenience in use and the like.