An optical head is provided which is capable of making an optical disk drive unit thinner. The optical head includes: a laser diode which emits light toward an optical disk; a photodiode which is disposed in the same housing as the laser diode; a light-turning mirror which reflects and deflects the light emitted from the laser diode; a light-raising mirror which reflects and deflects the light reflected by the light-turning mirror in the direction of the optical disk; an objective lens that converges the light reflected by the light-raising mirror onto the optical disk; and a hologram element which allows the light reflected by the optical disk to branch off and reach the photodiode, in which at least a part of the light-turning mirror is disposed inside of the window portion of a cartridge which houses the optical disk.