The utility model discloses a tunnel confined concrete bow member mechanical construction fixes a position vertical connecting device fast, including the fixed part and location guide adapting unit who is fixed in the bow member both sides respectively, just fixed part guides adapting unit coaxial with the location, and fixed part and location guide adapting unit's mounted position, direction are unanimous on the adjacent bow member, and just adjacent bow member passes through the connection of longitudinal register pole, and the fixed part of a pin bow member is connected to longitudinal register pole one end, and the location guide adapting unit of another pin bow member is connected to the other end to realize assembling the bow member and assembled the location of accomplishing between the bow member, fixed. The utility model discloses install convenient flexibility, easy to operate carries out bow member when location, only need two adjacent pin bow members butt joint can, save bow member installation time for the construction progress.