To constitute a latch member so as to be retractable even when a door lever is locked to unlock this retraction.

In this latch device 1 of the door provided with a latch operation mechanism 3 for moving the latch member 2 so as to come out and retract freely by turning the door lever 4 and a lock mechanism 5 for locking/unlocking the latch operation mechanism 3 in a casing 6, the latch member 2 is supported in the casing 6 so as to come out and retract freely, the lock mechanism 5 has a lock member 20 for locking/unlocking the latch operation mechanism 3 by moving between lock positions from a lock release position and a knob member 21 for moving the lock member 20, and a lock release means 36 for moving the lock member at the lock position to the lock release position by retraction of the latch member 2 is provided between the latch member 2 and the lock member 20.