The invention discloses a generation-absorption-reabsorption system and an absorption type unit based on the system, and belongs to the technical field of heat pump / refrigeration. The absorption type unit consists of an absorber, a second absorber, a generator, a solution heat exchanger, a second solution heat exchanger and one or two solution pumps, wherein the absorber is communicated with the generator via the solution pump and the solution heat exchangers, the generator is communicated with the second absorber via the second solution heat exchanger, and then the second absorber is communicated with the absorber via the solution heat exchanger; or the absorber is communicated with the second absorber via the solution pump and the solution heat exchanger, the second absorber is communicated with the generator via the second solution pump and the second solution heat exchanger, and then the generator is communicated with the absorber via the solution heat exchanger. The generator is provided with a cryogen steam pipeline and a driving heat medium pipeline respectively communicated with the outer part, and the absorber and the second absorber are respectively provided with a cryogen steam pipeline and a heated medium pipeline respectively communicated with the outer part. The generator provides high-temperature cryogen steam for the outer part, the absorber absorbs higher-temperature cryogen steam and releases the heat, the second absorber absorbs lower-temperature cryogen steam and releases the heat to form a generation-absorption-reabsorption system, and components are added to form the absorption unit based on the system.