A projection display apparatus according to embodiments includes a light source that emits color component light beams of a plurality of colors and an imager that modulates the color component light beams of a plurality of colors emitted from the light source. The projection display apparatus includes an element control unit that controls the imager; and a light source control unit that controls the light source. The element control unit controls the imager based on an image output signal obtained by a signal expansion process of an image input signal. The light source control unit performs a power reduction process of reducing power supplied to the light source according to an expansion amount of the image input signal expanded by the signal expansion process. The light source control unit performs a light emission period control process of adjusting light emission periods of a color component light beams of a plurality of colors emitted from the light source within a 1-frame period according to the image input signal.