According to the development of the lightweight night vision device in the world and accelerating the research of the lightweight night vision technique, a hybrid optical system of head-mounted display used for lightweight night vision is designed. The parameters of objective are ±14° field-of-view and f=1.4. This objective with one diffractive surface can be compatible with second and third generation image intensifying tube with size of 18 mm and planar type of input surface. The maximal value of distortion could be ignored for it is less than 0.5% of objective and can be used to accurately measuring and aiming. Considering the safety problem, A see-through monocular display system is designed to deliver the information of the image and the real world to human eye with a holographic combiner. The features of display the system are 15 mm (H)×10 mm (V) exit pupil size, 25 mm exit pupil and [±14° (H)]×[±10° (V)] field-of-view. The resolution and distortion of display system are 0.6 mrad and 3%, respectively, and it can be matched with display size of 18 mm.