Color-changing mark pen

The utility model discloses a color-changing mark pen which comprises a pen holder, pen points are arranged at the two ends of the pen holder, pen caps covering the pen points are further arranged at the two ends of the pen holder, an absorption rod is arranged on the pen points, two first sealing plates are arranged in the pen holder, an adjusting bin is formed between the two first sealing plates, and two second sealing plates are arranged in the pen holder. A light pigment bin is formed on the inner side of the second sealing plate, and a thick pigment bin is formed on the outer side of the second sealing plate; the absorption rod comprises an outer tube and an inner core, one end of the outer tube extends into the thick pigment bin, the other end of the outer tube is inserted into the pen point, one end of the inner core extends into the light pigment bin, the other end of the inner core penetrates through the outer tube and then is inserted into the pen point, a telescopic adjusting mechanism is arranged