To provide a locking check support device capable of preventing malfunction in the locking check support device equipped with a manual operation type key use sensor.

A portable type locking check support device is equipped with the manual operation type key use sensor 20. The manual operation type key use sensor 20 is constituted of a switch equipped with an electric contact 22, a time record operating hook 21 slidably mounted to a portable type case 1 by a predetermined distance as an operating member turning the switch ON in the case of operation and a coil spring 23 energizing so that the time record operating hook 21 can be separated from the switch in the case of non-operation. A key holder 2 is connected to an operating head of the time record operating hook 21 through a double ring 4. When a user pushes the time record operating hook 21 down, the present time at that time is memorized in a memory of an electric clock 10 as a locking check time.