An intake manifold of a multicylinder engine comprising: a manifold main body; an intake air introducing sleeve portion; and an EGR gas introducing passage, and configured such that when a longitudinal direction of the manifold main body is defined as a front-back direction, a passage outlet of the EGR gas introducing passage is provided on a front side or a back side of a sleeve portion peripheral wall of the intake air introducing sleeve portion and EGR gas is introduced from the passage outlet of the EGR gas introducing passage into the intake air introducing sleeve portion, wherein the intake manifold is configured such that an EGR gas guide portion is provided in the intake air introducing sleeve portion, the EGR gas guide portion includes a single upstream EGR gas release port and a single downstream EGR gas release port, the upstream EGR gas release port is provided on a side of the passage outlet of the EGR gas introducing passage, the downstream EGR gas release port is provided on an opposite side of a central portion of the intake air introducing sleeve portion from the upstream EGR gas release port, the EGR gas introduced from the passage outlet of the EGR gas introducing passage into the intake air introducing sleeve portion is released from both of the upstream EGR gas release port and the downstream EGR gas release port into intake air passing through the central portion of the intake air introducing sleeve portion, the upstream EGR gas release port opens with a smaller opening area than the downstream EGR gas release port, and the EGR gas guide portion includes a guide bottom wall and a guide peripheral wall, the guide bottom wall projects into the intake air introducing sleeve portion in a direction intersecting a central axis of the intake air introducing sleeve portion, the guide peripheral wall is led out from an opening edge portion of an intake air passing port surrounded with the guide bottom wall toward an inlet of the intake air introducing sleeve portion, the upstream EGR gas release port and the downstream EGR gas release port open on the guide peripheral wall, and an EGR gas guide clearance sandwiched between the sleeve portion peripheral wall of the intake air introducing sleeve portion and the guide peripheral wall is formed between the passage outlet of the EGR gas introducing passage and the downstream EGR gas release port. a manifold main body; an intake air introducing sleeve portion; and an EGR gas introducing passage, and configured such that when a longitudinal direction of the manifold main body is defined as a front-back direction, a passage outlet of the EGR gas introducing passage is provided on a front side or a back side of a sleeve portion peripheral wall of the intake air introducing sleeve portion and EGR gas is introduced from the passage outlet of the EGR gas introducing passage into the intake air introducing sleeve portion, wherein the intake manifold is configured such that an EGR gas guide portion is provided in the intake air introducing sleeve portion, the EGR gas guide portion includes a single upstream EGR gas release port and a single downstream EGR gas release port, the upstream EGR gas release port is provided on a side of the passage outlet of the EGR gas introducing passage, the downstream EGR gas release port is provided on an opposite side of a central portion of the intake air introducing sleeve portion from the upstream EGR gas release port, the EGR gas introduced from the passage outlet of the EGR gas introducing passage into the intake air introducing sleeve portion is released from both of the upstream EGR gas release port and the downstream EGR gas release port into intake air passing through the central portion of the intake air introducing sleeve portion, the upstream EGR gas release port opens with a smaller opening area than the downstream EGR gas release port, and the EGR gas guide portion includes a guide bottom wall and a guide peripheral wall, the guide bottom wall projects into the intake air introducing sleeve portion in a direction intersecting a central axis of the intake air introducing sleeve portion, the guide peripheral wall is led out from an opening edge portion of an intake air passing port surrounded with the guide bottom wall toward an inlet of the intake air introducing sleeve portion, the upstream EGR gas release port and the downstream EGR gas release port open on the guide peripheral wall, and an EGR gas guide clearance sandwiched between the sleeve portion peripheral wall of the intake air introducing sleeve portion and the guide peripheral wall is formed between the passage outlet of the EGR gas introducing passage and the downstream EGR gas release port.