Envelope opening knife pen

The utility model provided a letter-opening pen which comprises a pen holder which is provided with a location element which a letter opener is arranged on. The letter opener is made of plywood the edge of which is provided with a cutting groove which forms a grab. The end of the cut groove is provided with a fossa groove which is provided inside with a blade, the edge of which is connected with the end of the side of the grab. The letter opener can be detachably connected with a location element. The shape of the plywood on the letter-opening pen can be round or rectangle or oval or heart or pentagonal in order to match various shapes of pens. The letter-opening pen combines a pen with the letter opening device and has the letter-opening blade arranged on the plywood of the pen, which can be clamped in a pocket, thereby a user can carry the pen as well as the letter-opening blade to open a letter by cutting the sealed opening of the letter at any time. In addition, the utility model of a simple structure is