A method for joining a resin member and a porous member can prevent
peeling in a specified direction. When a thermoplastic laser transmitting
resin member and a porous member are joined, the laser transmitting resin
layer and the porous member are laminated, and a laser beam is emitted at
a side of the laser transmitting resin member. The porous member is
heated so that the laser transmitting resin member is melted, and the
melted resin is impregnated with holes of the porous member. The resin is
cooled so as to solidify.