An air intake apparatus comprising: an air intake apparatus body including an intake air passage (22a, 22b, 25a, 25b); and an external gas passage portion provided as a structure separate from the air intake apparatus body inside the air intake apparatus body, the external gas passage portion through which external gas can be introduced into the intake air passage (22a, 22b, 25a, 25b), wherein the external gas passage portion is arranged apart from an inner surface of the intake air passage (22a, 22b, 25a, 25b) by a space inside the air intake apparatus body, the intake air passage (22a, 22b, 25a, 25b) includes a plurality of intake air passages that is configured to distribute intake air to cylinders of an engine, respectively, the external gas passage portion has a tournament shape in which the external gas passage portion is hierarchically branched such that the external gas is guided to each of the plurality of intake air passages inside the air intake apparatus body, an external gas introduction portion that is configured to introduce external gas is provided on one side end of the air intake apparatus body, the external gas passage portion extends inward of the air intake apparatus body through the external gas introduction portion, and has an asymmetrical tournament shape with respect to a starting point for branching to be hierarchically branched, and a distance from each of starting points for branching of external gas (EGR gas) flow paths (42a to 42g) of hierarchies branched into the asymmetrical tournament shape to a next starting point for branching of the flow path through which the external gas flows in the same direction as the flow direction (X2 direction) of the gas introduced from the external gas introduction portion or an inlet (44, 45) is relatively longer than a distance from each of the starting points for branching of the external gas (EGR gas) flow paths (42a to 42g) of the hierarchies branched into the asymmetrical tournament shape to a next starting point for branching of the flow path through which the external gas flows in a different direction (X1 direction) from the flow direction (X2 direction) of the gas introduced from the external gas introduction portion or an inlet (43, 46). an air intake apparatus body including an intake air passage (22a, 22b, 25a, 25b); and an external gas passage portion provided as a structure separate from the air intake apparatus body inside the air intake apparatus body, the external gas passage portion through which external gas can be introduced into the intake air passage (22a, 22b, 25a, 25b), wherein the external gas passage portion is arranged apart from an inner surface of the intake air passage (22a, 22b, 25a, 25b) by a space inside the air intake apparatus body, the intake air passage (22a, 22b, 25a, 25b) includes a plurality of intake air passages that is configured to distribute intake air to cylinders of an engine, respectively, the external gas passage portion has a tournament shape in which the external gas passage portion is hierarchically branched such that the external gas is guided to each of the plurality of intake air passages inside the air intake apparatus body, an external gas introduction portion that is configured to introduce external gas is provided on one side end of the air intake apparatus body, the external gas passage portion extends inward of the air intake apparatus body through the external gas introduction portion, and has an asymmetrical tournament shape with respect to a starting point for branching to be hierarchically branched, and a distance from each of starting points for branching of external gas (EGR gas) flow paths (42a to 42g) of hierarchies branched into the asymmetrical tournament shape to a next starting point for branching of the flow path through which the external gas flows in the same direction as the flow direction (X2 direction) of the gas introduced from the external gas introduction portion or an inlet (44, 45) is relatively longer than a distance from each of the starting points for branching of the external gas (EGR gas) flow paths (42a to 42g) of the hierarchies branched into the asymmetrical tournament shape to a next starting point for branching of the flow path through which the external gas flows in a different direction (X1 direction) from the flow direction (X2 direction) of the gas introduced from the external gas introduction portion or an inlet (43, 46).