The invention discloses a device for recycling waste heat of automobile exhaust and belongs to the technical field of waste heat recycling. The device is mainly used for recycling the waste heat of the automobile exhaust for low-temperature start of automobiles, especially large diesel vehicles. The device is provided with a heat collector (6), a heat accumulator (11), a heat exchanger (22) and a first pipeline system. The heat collector (6) can be arranged on an exhaust emission pipe, the heat accumulator (11) is filled with phase-change heat storage materials (49), heat conduction oil (50) is used as a heat conduction working medium of the first pipeline system, and different circulation modes can be achieved according to needs. The heat exchanger (22) can transmit heat to the outside through an internally-arranged heat exchange unit with different heat conduction working media and different circulation pipelines and can greatly reduce abrasion caused during the process of low-temperature start of an engine. The device can achieve the purposes of saving energy and protecting the environment, transmit the heat for heating a target object and carry out centralized regulation and control. The device is capable of finishing low-temperature start of the automobiles, easy to manufacture, low in cost, convenient to install and use, free of influence on original automobile design and capable bringing convenience to standardized and industrialized production.