OPTICAL ELEMENT, VEHICLE LAMP MODULE, VEHICLE LAMP, AND VEHICLE

An optical element, comprising a light guide body. The light guide body comprises: a plurality of light-incident parts (1) arranged along a length extension direction of the light guide body; a light guide part (2); and a light-emitting part (3). Each light-incident part (1) is provided with at least one light-incident unit, the light guide part (2) is configured to guide light received by each light-incident unit to be emitted toward the light-emitting part (3). The shape of a forward projection plane of the light-emitting part (3) is of a strip shape. The optical element can reduce the occupied space and improve the space utilization rate, facilitates reducing positioning mounting errors, has an appearance with a narrow and elongated shape, and can be applied in vehicle lamp modules, vehicle lamps, and vehicles.