The optical module 1 is disposed on the optical element 30, the first substrate 10 on which the optical element 30 is mounted on the first main surface 10SA, and the second main surface 10SB of the first substrate 10. The holding member 40, the optical fiber 50 inserted into the through hole H40 of the holding member 40, the main surface 20SA are arranged in parallel to the main surface 10SA of the first substrate 10, and the wall surface H20SS is The holding substrate 20 having the opening H20 in contact with the outer peripheral surface 40SS of the holding member 40, the relay substrate 15 connecting the first substrate 10 and the holding substrate 20, and the main surface 25SB have the optical axis O. Are arranged in parallel with each other, the end portion of which is connected to the holding substrate 20 and the electrode 21 is disposed on the main surface 25SB, the electrode 21 of the side substrate 25, and the tip portion are joined together. The signal cable 60 To Bei.光モジュール１は、光素子３０と、第１の主面１０ＳＡに前記光素子３０が実装されている第１の基板１０と、前記第１の基板１０の前記第２の主面１０ＳＢに配設されている保持部材４０と、前記保持部材４０の貫通孔Ｈ４０に挿入されている光ファイバ５０と、主面２０ＳＡが第１の基板１０の主面１０ＳＡに平行に配置されており、壁面Ｈ２０ＳＳが保持部材４０の外周面４０ＳＳと当接している開口Ｈ２０のある保持基板２０と、前記第１の基板１０と前記保持基板２０とを接続している中継基板１５と、主面２５ＳＢが光軸Ｏに平行に配置され、端部が前記保持基板２０と接続され、主面２５ＳＢに電極２１が配設されている側面基板２５と、前記側面基板２５の前記電極２１と、先端部が接合されている信号ケーブル６０と、を具備する。
