The invention discloses an eyepiece and a head mounted display device. The eyepiece comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are arrayed in parallel sequentially between an aperture slot and a display screen, wherein the second lens and third lens form a glued lens group, the other lenses are separately arranged. The first lens, third lens and the fourth lens are plus lenses, the second lens is a minus lens, the fifth lens is a plus lens, the sixth lens is a minus lens, or the fifth lens is a minus lens, the sixth lens is a plus lens. The eyepiece can acquire a big rear cut-off distance, and supports Myopia regulation in a wide range. Myopic people can see images clearly without wearing myopia lenses. At the same time, the eyepiece is compact in structure, has a big exit pupil diameter and a big exit pupil distance, permits certain level of wearing deviation, possesses a big viewing angle and small distortion, a high transfer function and a small color difference, and can guarantee the image clarity and color expressiveness.