Locking mechanism and connector group

The invention provides a locking mechanism and a connector group, which can realize miniaturization of a connector and an installation space of the connector and can improve operability when the connector is inserted and pulled out. The lock mechanism is configured so as to maintain a fitted state between a first connector and a second connector that can be fitted to the first connector, and is provided with: a lock member that has an engagement portion and is provided to the first connector; a biasing part connected to the lock member and holding the lock member in a reference state; a rotating shaft which is disposed parallel to a direction orthogonal to the fitting direction and supports the lock member such that the lock member can rotate; and an engagement receiving portion provided on the second connector and engageable with the engagement portion, the lock member being attached to the first connector so as to be rotatable about the axis of rotation. 本发明提供能够实现连接器及连接器的安装空间的小型化，并且能够提高连接器的插入时及拔出时的作业性的锁定机构及