A projection-type image display apparatus includes a light source, an optical modulator, a projection lens assembly, a power supply board, a sealed housing, a heat exchanger, a partition, and a fan. The optical modulator modulates the light from the light source to generate image light. The projection lens assembly has a plurality of lenses and projects the image light. The power supply board drives and controls the light source. The sealed housing houses the light source, the power supply board, the optical modulator, and the projection lens assembly. The heat exchanger exchanges heat between gas inside the sealed housing and gas outside the sealed housing. The partition is disposed inside the sealed housing and divides the inside of the sealed housing into a first space and a second space. The fan sequentially sends the gas inside the sealed housing from the heat exchanger through the first space to the second space.