A night vision device, comprising a first light-sensitive chip, a first lens group (101), a first display screen, an image processing system and a control system for adjusting an imaging range of the first light-sensitive chip by adjusting times of optical zooming of the first lens group and/or digital zooming of the image processing system. The night vision device further comprises an auxiliary illumination module (103), which comprises an auxiliary light source and a light guiding cavity; the auxiliary light source at least can emit infrared light; a light ray emitted by the auxiliary light source is emitted via the light guiding cavity; the light guiding cavity has a movable adjustment component for adjusting an irradiation range of the emitted light ray in a manual manner or by means of automatic control by the control system; and the irradiation range is adapted to the imaging range of the first light-sensitive chip. The night vision device according to the present invention can improve a night visual range and imaging quality without changing the level of hardware.