To provide a rucksack completely preventing the intrusion of rainwater and suited for cases where stored objects are not frequently taken in/out such as a mountain stream climbing or a cargo discharge.

This rucksack for the mountain climbing comprises a storage body A having an opening part and formed into a bag shape; and a body having cover bodies 12, 14, 16, 18, 20 and 22 which have fastening bands 13, 15, 17, 19, 21 and 23 with locking implements in their respective ends at both ends of a core body 11 formed into a belt shape, and having at least a pair of cover body provided with the fastening bands with the locking implements at their respective ends on both sides of the core body: and is provided with the storage body formed into the bag shape on the body back part having a shape for wrapping into a cloth wrapper and a shoulder belt for carrying or a shoulder belt D and a waist belt C in arbitrary positions. This constitution can solve problems that a rucksack is designed to relatively easily take in/out the stored objects, however, the parts to be sewn are many and the shape is complicated, which cause an increase in cost of processing charge, and further consideration is required therefor such as attaching a rain visor for improving the waterproof property of the opening part.