A connector assembly comprises a first connector and a second connector matable with the first connector in a mating direction. The first connector includes a housing and a slider held by the housing and slidable with respect to the housing in a direction intersecting the mating direction. The slider has a slider backlash restraining device disposed on an inner wall. The slider slides in a first direction to cause the second connector to move in the mating direction and slides in a second direction opposite to the first direction to cause the second connector to move in a direction opposite to the mating direction. The second connector has a connector backlash restraining device disposed on an outer wall of the second connector. The slider backlash restraining device abuts the connector backlash restraining device when the first connector is mated with the second connector.