A filter for gas generator has an outer geometry substantially of a hollow cylinder and it is formed by a wound body of a metal wire. The metal wire is made of an elongated member having a V-shaped cross-section orthogonal to a direction of extension thereof. A V-shaped groove defined in the metal wire faces a hollow portion in the filter for gas generator and an angle α of the V-shaped groove is not smaller than 130[°] and not greater than 140[°].