Abstract: A device for recovering the refrigeration units of LNG (liquid natural gas) used as fuel in vehicles is disclosed. The device can include: a first heat exchanger placed on a tractor of the vehicle between a LNG tank and a LNG gasification and heating circuit, said LNG being sent to a motor of the vehicle; a second heat exchanger placed inside a refrigerated cabin of a trailer or semi-trailer of the vehicle; and a closed intermediate circuit, in which a heat transfer fluid flows, which includes an apparatus for moving the heat transfer fluid, systems for connecting and disconnecting the pipelines of the intermediate circuit which are installed on the tractor with/from the pipelines of the same intermediate circuit installed on the trailer or semi-trailer and apparatus for storing and re-integrating the heat transfer fluid in the intermediate circuit and for maintaining the heat transfer fluid at a certain pressure value in said intermediate circuit.