The invention discloses a heat sink suitable for a disc laser jet flow impingement cooling system. The heat sink includes a rib base and a plurality of ribs distributed on the rib base; the rib base serves as a carrier of a disc laser crystal, one end face of the rib base is used for fixing the disc laser crystal, and the coaxially arranged ribs are distributed on the other end face; and the ribs are used for increasing a heat radiation area, and reducing convection heat exchange heat resistance. When the heat sink is applied to the laser jet flow impingement cooling system, a lower surface of the heat sink performs heat exchange through jet flow impingement cooling, the ribs of the lower surface increases the superficial area of convection heat exchange, thereby increasing the heat exchange rate; and in addition, the ribs also increase the strength of the whole heat sink in terms of structure, and play a role of dispersing jet flow pressure, and can reduce impingement deformation of a disc.