A liquid-cooled heat sink head includes a metal substrate, a first cover, and a plurality of heat dissipation fins. The first cover covers the metal substrate to form a heat exchange chamber and includes a first liquid inlet and a liquid outlet to allow a working fluid to flow in the heat exchange chamber. The heat dissipation fins are disposed on the metal substrate, are placed between the first liquid inlet and the liquid outlet, and are arranged sequentially from the first liquid inlet toward the liquid outlet. A liquid passage is disposed between each two adjacent heat dissipation fins. A portion of the heat dissipation fins are connected to the heat exchange portion, and at least one heat dissipation fin includes one opening to communicate with the liquid passages at two sides of the at least one heat dissipation fin.