The invention provides a large-relative aperture near-infrared common-path double-field athermal optical imaging system. A front fixed lens group is composed of a positive lens, a negative lens and a positive lens which are arranged sequentially after the object surface and connected fixedly. A back fixed lens group is composed of a positive lens, a negative lens, a positive lens, a positive lens and a negative lens in sequence. The front fixed lens group and the back fixed lens group are stationary in the process of zooming. A middle zoom lens group is composed of a first cemented lens group and a third negative lens, and the first cemented lens group is formed by cementing a negative lens and a positive lens together. The zoom lens takes a motor fixedly connected to the lens cone as a drive source, is driven by a gear-guide rail mechanism, moves forward and backward along the optical axis to realize two-gear double-field zooming, and forms the optical imaging system together with the front fixed lens group and the back fixed lens group. An optical athermalization technology is adopted in the invention. The system is switched between two gears and double fields, and the total length remains unchanged. When imaging the same scene, the system has good imaging quality without focusing in a temperature range from -40 DEG C to 60 DEG C.