An optical module is configured such that it is not susceptible to fine particulate matter when an optical fiber is inserted into a fiber insertion hole thereof. The optical module is also configured to prevent any reduction in the optical coupling efficiency and degradation of anti-noise properties with the optical fiber. The optical module includes: a ferrule, having the fiber insertion hole formed on an end surface on which an electrical circuit is formed; a photoelectric conversion element, connected to the electrical circuit and facing the fiber insertion hole; and an optical fiber, optically coupled directly with the photoelectric conversion element. The optical fiber has a glass fiber and a protective coating, and is aligned with the insertion hole with the protective coating interposed therebetween. The optical fiber is retained in the insertion hole with the glass fiber not in contact with the insertion hole.