An air intake apparatus for the internal combustion engine is disclosed comprising a heating resistor placed in a bypass for passing the air of an amount in a predetermined ratio to the amount of the air passing through a main air path communicating with the internal combustion engine, the bypass circumventing or detouring the main air path. The bypass body for defining the bypass is made of a synthetic resin material in order to prevent heat conduction to the heating resistor from an external source.