An optical transmission module is provided which has excellent long-term reliability, high manufacturing efficiency and a smaller optical output loss and which facilitate its downsizing, weight saving and high integration. The optical transmission module is provided with a first optical device 118 placed on an output side, a second optical device 122 placed on the first optical device 118 aligned with an optical axis of the first optical device 118, a package 111 including the first and second optical devices 118 and 122, and an optical fiber 115 configured to guide light emitted from the first optical device 118 to the outside of the package 111. The first optical device 118 and the second optical device 122 are in close contact with each other on the surface perpendicular to the optical axis.