The invention discloses a double-cam-shaft switch supporting point type mode-switching valve driving system and belongs to the field of engine valve driving, cylinder deactivation and auxiliary braking. The system mainly comprises an intake valve assembly, an exhaust valve assembly, an exhaust braking cam, an exhaust driving cam, an intake driving cam, an intake braking cam, an exhaust braking rocker arm, an exhaust driving rocker arm, an intake driving rocker arm, an intake braking rocker arm, an exhaust braking supporting point assembly, an exhaust driving supporting point assembly, an intake driving supporting point assembly and an intake braking supporting point assembly. By controlling the states of all supporting points, various modes of four-stroke driving, two-stroke braking, cylinder deactivation and the like are achieved, and low-oil-consumption, low-emission and efficient braking is achieved. The double-cam-shaft switch supporting point type mode-switching valve driving system is oriented to actual application, the number of moving parts is small, the structure is simple and compact, the reliability is high, the cost is low, and the energy consumption is low.