PURPOSE: To realize bonding method having corrosion resistance in bonding faces of parts to be bonded and capable of retaining prescribed bonding strength.

CONSTITUTION: Outer area of bonding faces of bonding parts 1 and 2 to be bonded is bonded by a bonding insert material 32 and inner area thereof is bonded by a bonding insert material 31 having high bond strength. Thereby the objective combination type bonding method capable of retaining sufficient bonding strength by the bonding insert material 31 in the inner area is realized without corroding these bonding faces with a corrosive gas by corrosion resistance and bonding function of the bonding insert material 32 in the outer area.