A wearable hand exoskeleton device comprises a fixing base, a thumb mechanism, an index finger mechanism, a middle finger mechanism, a ring finger mechanism and a little finger mechanism. The thumb mechanism, the index finger mechanism, the middle finger mechanism, the ring finger mechanism and the little finger mechanism are identical in constitution, and each comprise a tail-end fingerstall, a first linkage rod, a second linkage rod, a near-end fingerstall and a sliding rod all of which are sequentially connected through rolling bearings. The sliding rods of the finger mechanisms are connected with sliding slots in the hand back fixing base. Through the structure, the number of degrees of freedom of the hand exoskeleton device can be matched with the number of hand joints, and moving flexibility of the fingers is ensured. By means of the wearable hand exoskeleton device, the structure design of the hand exoskeleton is simplified, and the wearable exoskeleton device is convenient to use, small in occupied space, low in manufacturing cost and capable of being applied to the fields of force feedback gloves, hand rehabilitation devices, humanoid manipulators and the like.