Liquid cooling device

The invention relates to a liquid cooling device, which comprises a cover plate and a substrate, the cover plate is fixed on the substrate, the substrate comprises a plurality of flow collecting grooves, streamline grooves, circulation grooves and fins, the flow collecting grooves are positioned at two ends of the substrate, a water inlet and a water outlet are respectively arranged at two ends of the cover plate, and the streamline grooves are communicated with the circulation grooves. The water inlet and the water outlet are located above the flow collecting grooves, the fins are evenly distributed in the base plate in a rectangular array mode, the streamline grooves are distributed in the base plate at equal intervals, the two ends of each streamline groove are shrunk and correspondingly converge at the flow collecting grooves at the two ends of the base plate, and the adjacent streamline grooves are communicated through the circulation grooves. The number of the circulation grooves is multiple. Compared w