To provide an optical fiber coupler which excels in mechanical and optical characteristics, and to provide a method of manufacturing the optical fiber coupler with a high yield and at a low cost, by fixing on a reinforcing substrate an optical fiber containing a weld and drawn part by a four-point fixing method without using a divided substrate that deteriorates the strength.

The optical fiber coupler is constituted such that bundled plural optical fibers are heated and drawn to form a weld and drawn part 5, which is stuck and fixed to a reinforcing substrate; that the reinforcing substrate consists of the first substrate 1 for fixing a bare fiber 6 on both sides of the weld and drawn part 5, and the second substrate 2 for supporting the first substrate 1 as well as fixing the coating part 8 of the optical fiber on the outside of both ends in the longitudinal direction of the first substrate 1; and that a cushioning layer 4 is provided between the first and second substrates 1, 2.