An image projection system includes a translucent screen, a projector that projects image light to the translucent screen, and a controller that controls the projector and the translucent screen. The translucent screen includes a first light control film configured to be switchable between a transmissive state for transmitting incident light therethrough and a diffusion state for diffusing incident light, and a second light control film configured such that the transmittance thereof with respect to incident light can be changed. The controller has: a first mode in which, in the state where the projector does not project image light, the first light control film is in the transmissive state and the second light control film is in the state of having transmittance for transmitting incident light therethrough; and a second mode in which, in the state where the projector projects image light, the first light control film is in the diffusion state and the second light control film is in the state of having transmittance lower than the transmittance in the first mode. The controller is settable to the first mode or the second mode.