The invention provides a gas-liquid two-phase mixed jet micro-channel heat sink. The heat sink comprises an upper cover plate, a gas-liquid mixed jet structure, a micro-channel plate, a heater and a base, wherein the gas-liquid two-phase mixed jet structure comprises a cooling liquid inlet, a cross-flow liquid inlet, a jet entry cavity, jet holes and a gas-liquid mixed flow outlet. Cooling liquidfirst flows in from the cooling liquid inlet, a part flows to the micro-channel plate through the cross-flow liquid inlet to form cross-flow liquid for heat exchange, and the other part flows to the jet entry cavity, mixes with gas flowing in from an inlet port, then is jet to the micro-channel plate through the jet holes for heat exchange, and is simultaneously mixed with the cooling liquid flowing from the cross-flow liquid inlet to micro-channels, so that the cooling liquid in the micro-channels is disordered, and finally flows out from the gas-liquid mixed flow outlet. The cross-flow liquid in the micro-channels is impacted by gas-liquid two-phase mixed jet to realize enhanced heat transfer and suppress micro-channel boiling instability. In addition, the heat sink also has the characteristics of compact structure, small size, simple manufacturing process and the like.