A robotic arm capable of reducing the size while suppressing damage to a plurality of elongated members inserted therein, is provided. The robotic arm to which an end effector is attached, includes plurality of elongated members extending to end effector, cylindrical housing defining a periphery of internal space configured to be a passage of plurality of elongated members, and an attaching structure provided to a tip end of the internal space of the cylindrical housing so as to attach the end effector to a tip-end part of the cylindrical housing. The attaching structure includes insertion holes formed corresponding to plurality of elongated members so as to insert the plurality of elongated members therein, and fixing members configured to fix the plurality of elongated members to the insertion holes, respectively. The cylindrical housing is formed so that the inner diameter is larger at the tip-end part than at a base-end part.