To provide a folding knife with a finger hook in which a blade of the folding knife can be surely opened by one hand even when the finger is under an easily slipping condition or under a condition where a hand glove is worn.

The folding knife is characterized by providing a U-shaped cutout (2) from a ridge side of the blade (1) of the folding knife and providing a projection (3) on the ridge part. When this knife is used, opening and closing of the blade is easily performed either by pressing the cutout (2) part with a finger or hooking a finger or a part of a clothing on the projection (3) of the ridge part.