An optical-fiber assembly, optical coupling device and optical-fiber coupling device provided with optical-fiber assembly. In the optical-fiber assembly, damaging a fixing material is prevented by preventing clad mode light from being incident on the fixing material and direct incidence, on the fixing material; of laser light emitted from a light-emitting element or an optical-fiber is prevented to generate resistance to the emitted light. The optical-fiber assembly constitutes by at least an optical-fiber and capillary. The optical-fiber is inserted into the capillary and one optical-fiber end is protruded outside the capillary. The optical-fiber outer periphery and capillary are fixed using fixing material and ceramic material disposed to be in contact with the entire optical-fiber outer circumference and have predetermined contact length in the optical-fiber axial direction. The position at which the ceramic material is set in front of the position of the fixing material as viewed from one optical-fiber end.