To facilitate the setting of a product without sticking of adhesive to an opposite article during product positioning so as to secure a stable sealing force by composing joint sealant used for cutting-off water in the joint part of a concrete product of adhesive and a porous film stuck to the surface of the adhesive.

Sealant A is composed of a base material 1, adhesive 2 and a porous film 3, the base material 1 is formed to be a long material roughly circular in section and, for the adhesive 2, rubber based adhesive or the like having adhesiveness in a room temperature and in a non-solvent state is used. The porous film 3 having holes 31 formed by specified pitches is wound on the surface of the adhesive 2. For connecting concrete products 5 together by such sealant A, the sealing material A is provided in the joint parts of the concrete products 5 and, after the setting position of the sealant A is secured by repeating product positioning, the connecting surfaces of the concrete products 5 are brought to each other and bonded and, at this time, the joint parts are sealed by the adhesive 2 pushed from the holes 3 to the outside.