The invention discloses a single-efficiency absorption type refrigerating device with an expander-compressor, comprising a generator, a preheater, a rectifier, a condenser, a second throttle valve, an evaporator, an expander-compressor, an absorber, a solution pump, a solution heat exchanger, a fourth throttle valve and two middle heat exchange parts, wherein the generator, the preheater, the rectifier, the condenser, a first middle heat exchange part, the second throttle valve, the evaporator, the expander-compressor, the absorber, the solution pump and the solution heat exchanger are sequentially connected; the generator, the second middle heat exchange part, the solution heat exchanger, the fourth throttle valve and the absorber are sequentially connected; a gas-phase outlet of the first middle heat exchange part, the preheater, the expander-compressor and the absorber are sequentially connected; and a gas-phase outlet of the second middle heat exchange part, the expander-compressor and the absorber are sequentially connected. In the invention, work produced by the device is utilized to compress steam at the outlet of the evaporator to improve the working pressure of the absorber so as to ensure that the device can prepare cold quantity having a higher grade than that prepared by a traditional single effect absorption type refrigerating device.