An internal combustion engine comprising: a cylinder defining a combustion chamber; an intake valve including a valve body, and the valve body including an umbrella section; an exhaust port; and an intake port including a main flow passage section and a throat section, the main flow passage section being configured to distribute intake air toward the combustion chamber, the main flow passage section communicating with the combustion chamber via the throat section, and the throat section including a valve seat on which the valve body of the intake valve is seated, wherein the main flow passage section includes a first surface and a second surface, the first surface is located on a combustion chamber side of the main flow passage in a side cross-sectional view of the intake port, and the second surface facing the first surface, the first surface has a linear shape, a first extended line (A 1) is located on a side, opposite from the combustion chamber, of an exhaust port side portion of the umbrella section when the intake valve is in a state of a maximum lift amount, wherein the exhaust port side portion is a portion of the umbrella section closest to the exhaust port and the first extended line is defined by extending an end of the first surface toward the combustion chamber, a crossing position between the end of the first surface and the throat section has a bent shape, and a second extended line (A 2) is located at the combustion chamber side rather than a portion of the valve seat, the portion is the closest portion of the valve seat to the exhaust port, and the second extended line being defined by extending a middle line located at the middle of the first surface and the second surface toward the combustion chamber. a cylinder defining a combustion chamber; an intake valve including a valve body, and the valve body including an umbrella section; an exhaust port; and an intake port including a main flow passage section and a throat section, the main flow passage section being configured to distribute intake air toward the combustion chamber, the main flow passage section communicating with the combustion chamber via the throat section, and the throat section including a valve seat on which the valve body of the intake valve is seated, wherein the main flow passage section includes a first surface and a second surface, the first surface is located on a combustion chamber side of the main flow passage in a side cross-sectional view of the intake port, and the second surface facing the first surface, the first surface has a linear shape, a first extended line (A 1) is located on a side, opposite from the combustion chamber, of an exhaust port side portion of the umbrella section when the intake valve is in a state of a maximum lift amount, wherein the exhaust port side portion is a portion of the umbrella section closest to the exhaust port and the first extended line is defined by extending an end of the first surface toward the combustion chamber, a crossing position between the end of the first surface and the throat section has a bent shape, and a second extended line (A 2) is located at the combustion chamber side rather than a portion of the valve seat, the portion is the closest portion of the valve seat to the exhaust port, and the second extended line being defined by extending a middle line located at the middle of the first surface and the second surface toward the combustion chamber.