PROBLEM TO BE SOLVED: To provide an optical fiber holding member having excellent reliability while enabling an optical fiber to be precisely fixed.SOLUTION: An optical fiber holding member 40 comprises a through hole 40H which has an optical fiber inserted thereto, with the optical fiber fixed by resin, and also comprises a first base material 41 of a rectangular parallelepiped having a groove with a square cross section on a principal face 41SA, and a second base material 42 of a rectangular parallelepiped which has a joining face 42SA of the same size as the principal face 41SA of the first base material 1, with the joining face 42SA joined to the principal face 41SA.【課題】光ファイバを高精度に固定可能でありながら信頼性に優れた光ファイバ保持部材を提供する。【解決手段】光ファイバ保持部材４０は、光ファイバが挿入され樹脂で固定されている貫通孔４０Ｈを有し、断面が正方形の溝を主面４１ＳＡに有する直方体の第１の基材４１と、第１の基材４１の主面４１ＳＡと接合された、主面４１ＳＡと同じ大きさの接合面４２ＳＡを有する直方体の第２の基材４２と、を有する。【選択図】図２
