Optical module manufacturing method and optical module

A photo-electronic part is mounted at an accurate position on a waveguide substrate to reduce loss of propagating light and electrodes of the waveguide substrate and the photo-electronic part are electrically connected. A light deflection element (20) has a conductive substrate (21) and prism type electrodes (23a, 23b) sandwiching an optical waveguide (22). The waveguide substrate (10) has an indentation (13) where optical waveguides (12a, 12b) and the light deflection element (20) are mounted. At the bottom of the indentation (13), there are provided electrodes (14a, 14b). On the bottom of this indentation (13), a plenty of conductive spherical elastic bodies (30) are distributed. After this, in the indentation (13), the light deflection element (20) is arranged to press the spherical elastic bodies (30) and positions of the optical waveguides (12a, 12b) of the waveguide substrate (10) and the optical waveguide (22) of the light deflection element (20) are adjusted. While maintaining the correctly adjusted state, the light deflection element (20) is fixed to the waveguide substrate (10) by an optical adhesive (40).