To reduce costs for transporting and building a concrete cask.

This concrete cask 1 is provided with a cask body 4, cylindrically formed to accommodate a canister 3 having spent fuel enclosed and provided with bleeders 16, 21 in upper and lower parts such that air can be ventilated around the canister 3 accommodated, and a lid body 6 for closing an upper opening provided for taking the canister 3 in/out f the cask body 4. The cask body 4 is structured by sectionally dividing so as to form multiple stages in a vertical direction, and each parts block 4A, 4B, 4C divided is integrally fastened and secured by a tie rod 23 vertically penetrates all the parts blocks 4A, 4B, 4C divided and nuts 24, 25 tightened at both ends of the tie rod 23.