Connector locking device

A connector locking device, comprising:

• a first connector;
• a second connector coupled to the first connector, wherein the second connector comprises a guide hole having a locking protrusion and a locking groove on an outer side of the guide hole;
• a connector position assurance (CPA) member configured to be fastened to the locking groove while moving along the guide hole and configured to prevent the first connector and the second connector from being decoupled;
• and
• a slider mounted on the second connector to advance or retract in a direction intersecting a fastening direction of the first connector and the second connector, wherein the slider comprises a mating guide protrusion,
• wherein the CPA member comprises a mating guide groove configured to accommodate the mating guide protrusion such that the mating guide protrusion is inserted and movable in the mating guide groove, and
• the CPA member is configured to be guided to advance or retract in a direction intersecting the advancement or retraction of the slider.