To provide a projector for executing frame feed operation of a film over a long time by smooth intermittent operation, and to provide a three-dimensional video projection system that uses the projector.

The projector includes a beam light-generating means 11, a shutter member 9, a shutter-driving means 12, a pair of first guide reels 14 and 15, on which the film 13 is suspended, and an intermittent guide reel 16 that is arranged on a further downstream side of one first guide reel 14 which is arranged on the downstream side of the feed direction D and rotated and driven intermittently, a first reel driving means 17, consisting of a parallel cam mechanism for rotating and driving the intermittent guide reel intermittently frame by frame; a pair of second guide reels 18 and 19 that are arranged on the downstream side of the intermittent guide reel and on the upstream side of the other first guide reel 15; and a second driving means 20 for continuously rotating and driving the pair of second guide reels, in the rotation direction in synchronsm with the shutter-driving means and the first reel-driving means.