Intake device for internal combustion engine

According to one aspect of the invention, there is provided an intake device for an internal combustion engine including a gas passage unit (30) defining therein a secondary gas supply passage (31) for supplying a secondary gas to an intake of the engine (10), and a thermal insulator (51) disposed over at least one side of the gas passage unit (30) so as to thermally insulate the secondary gas supply passage (31).