The invention discloses a high and low temperature resistant medium wave infrared optical window and a manufacturing method thereof, relating to an optical window and a manufacturing method thereof, and solving the problem of blurry optical imaging caused by that the temperature gradient at two sides of the window is easy to lead the window to be frosted at the normal temperature when the currentoptical window is a in high and low temperature test. The high and low temperature resistant medium wave infrared optical window is composed of pieces of aluminized paper, two monolayer hot-pressing window plates, a space ring and dry nitrogen, wherein, the two monolayer hot-pressing window plates are oppositely arranged in parallel, and are separated by the space ring so as to form a seal interlayer with the space ring; the seal interlayer is filled with the dry nitrogen; the pieces of aluminized paper are arranged on the two monolayer hot-pressing window plates and at the outside periphery of the space ring; and the manufacturing method of the optical window finishes manufacturing the optical window mainly through the steps, such as cleaning, gluing and aerating and the like. The invention is suitable for the high and low temperature optical test field.