A projection apparatus includes an image projection module, a lens module and a light emitting module. The image projection module has a first optical axis and forms a projection area on a bearing surface. A projection of the first optical axis on an X-Z plane is perpendicular to an X-Y plane on which the projection area is formed. The lens module comprises N cameras, each having a corresponding second optical axis and being for forming a shooting area. The N second axes are tilted to the first optical axis and have an angle with respect to the X-Z plane. The light emitting module includes M light emitting components, each having a corresponding third optical axis and being for forming a sensing area. The projection area, the N shooting areas and the M sensing areas are at least partially overlapped with each other to form a rectangular shooting sensing area.