A liquid cooling plate used for electronic component cooling comprises a substrate and a cover plate. The substrate is provided with a plurality of parallel straight grooves. The adjacent front and back straight grooves are connected in an end to end mode, and the straight grooves are connected through connection grooves. The straight grooves and the connection grooves are transited through arcs. The straight grooves on the substrate, the connection grooves and the cover plate form a channel where a cooling liquid flows. A bottom wall of each straight groove is provided with a first groove. A width of the first groove occupies 60%-80% of a channel width. The liquid cooling plate possesses advantages that liquid cooling plate temperature rise and cooling liquid pressure drop are considered; and the liquid cooling plate temperature rise and the cooling liquid pressure drop are simultaneously greatly reduced.