A light valve angle dynamic adjustment device for a projector includes a light valve, a first movable portion, a first motor and a first mechanism. The light valve is arranged on a support of the first movable portion. The first motor is capable of driving the first mechanism. The first movable portion is also provided with a first rotation axis and a first mating portion. The first motor is capable of driving the first mechanism to make the first movable portion swing around the first rotation axis through the first mating portion.