A projection apparatus includes a casing, a motherboard, a power board, a light source, and a projection lens. The motherboard includes a host circuit board, a light valve, and a CPU, and is contained inside the casing. The light valve and the CPU are on the host circuit board. The power board includes a power circuit board and an AC/DC power module. The power circuit board is contained inside the casing, and the AC/DC power module is on the power circuit board. The light source is used to produce an illuminating beam. The light valve is used to transform the illuminating beam into an image beam. The projection lens is used to transform the image beam into a projecting beam. The power circuit board is parallel to the host circuit board. An optical axis of the projection lens is perpendicular to the host circuit board and power circuit board.