Myopia preventing pen

The utility model discloses a myopia preventing pen, which comprises a pen head, a pen rod and a pen core. A photoelectric sensor and an alarming lamp are equipped on the pen rod. A buzzing alarm is equipped inside the pen rod. A battery and an alarming circuit are also equipped inside the pen rod. A power switch is equipped on the pen rod. The photoelectric sensor, the alarming lamp, the buzzing alarm and the battery are respectively connected with the alarming circuit. The utility model is capable of sensing the environmental luminous intensity and meanwhile sensing the slight light change when the eyes of a writer are too close to the paper and then reminding the writer of adjusting the distance between the eyes and the paper. The utility model has a myopia preventing function added on the basis of a common pen.