An optical module is provided in which recesses are formed in a sol-gel layer applied to a surface of a lens array substrate, each of the recesses having a capability to fit an optical fiber therein. The optical module comprises a planar microlens array substrate having a plurality of microlenses formed in one surface thereof; and an alignment recess array including a plurality of alignment recesses which are formed in a material applied to the other surface of the microlens array substrate by means of a mold with the center of each alignment recess being aligned to the center of a corresponding one of the microlens. The optical module may comprise a plurality of optical fibers each end thereof is adhered to the alignment recesses.