The present invention provides a connection module that allows miniaturization of a coupling structure for insulating protectors. A connection module includes a plurality of bus bars and a plurality of insulating protectors that insulate and hold the plurality of bus bars. Each of the insulating protectors includes at least one of a lock portion that includes a lock protrusion and that is provided for coupling with an adjacent insulating protector and a guide portion that guides the lock protrusion of the lock portion provided in the adjacent insulating protector such that the lock protrusion is engaged with the guide portion. The lock portion includes a guide receiving portion into which the guide portion is to be inserted, and the guide portion includes a lock engagement portion with which the lock protrusion is to be engaged.