An aspect of the present invention is an optical element that combines light waves using a spatial optical system, including a housing section, an optical waveguide element, a combine section, and a collimator section is provided. The housing section has a storage space and is formed by joining two or more members together. The optical waveguide element is provided in the storage space and emits at least two light waves. The combine section is provided outside the storage space and combines the light waves emitted from the optical waveguide element outside the housing section using a spatial optical system. The collimator section is connected to the housing section, holds the combine section, and includes a light focusing section configured to focus a light wave combined by the combine section and an optical fiber to which the light wave focused by the light focusing section is introduced.