The present invention provides active shutter glasses including shutters in which orientations of their components are freely determined, and provides a stereoscopic image projection system. The present invention provides active shutter glasses for a stereoscopic image projection system, the active shutter glasses comprising: a right-eye shutter; and a left-eye shutter, wherein the right-eye shutter and the left-eye shutter each include a liquid crystal layer and a linear polarizing element, at least one of the right-eye shutter and the left-eye shutter includes a layer adopted to change a vibration direction of polarized light, the linear polarizing element is provided at the outer side of the liquid crystal layer, and the layer adapted to change a vibration direction of polarized light is provided at the outer side of the linear polarizing element.