Embodiments of the invention provide a liquid-cooling heat dissipation system and laser projection equipment, and relate to the field of liquid-cooling heat dissipation. With the system and the equipment, bubbles inside pipes are reduced, the occurrence of cavitation phenomenon is avoided, the noise of the system is reduced, and the performance of the system is improved. The liquid-cooling heat dissipation system comprises a heat absorption device, a drive device and a heat dissipation device which are connected through a pipe. The liquid-cooling heat dissipation system further comprises a pressurization device which is composed of a piston and a cylinder matching the piston. One side of the piston is in contact with cooling liquid in the liquid-cooling heat dissipation system. A force applying object is arranged on the piston, and the force applying object can apply a force to the piston to make the piston squeeze the cooling fluid. The pressurization device is connected to the flow path of the cooling liquid through the cylinder. The liquid-cooling heat dissipation system is used for equipment heat dissipation.