A propeller fan (5; 25) comprising: a hub including a side surface around a center axis; and a plurality of blades disposed on the side surface of the hub, wherein the blades each include a blade surface part extended from a base end connected to the side surface of the hub to an outer edge, and the blade surface part includes an inner peripheral part positioned on the base end side and an outer peripheral part positioned on the outer edge side, an inner peripheral blade (15; 35), which extends from the side surface of the hub toward the outer edge side, is formed on a positive pressure surface of the blade surface part at the inner peripheral part of each of the blades, the inner peripheral blade (15; 35) projects from the positive pressure surface of the blade surface part toward a positive pressure side, and includes a front edge (15a-F; 35a-F) in a rotation direction of the inner peripheral blade (15; 35) that is formed in a curved shape to be separated from a straight reference line toward a front edge (12-F) side in a rotation direction of the blade, the straight reference line connecting a lower end (E3; E4) positioned on the positive pressure surface at the base end of the inner peripheral blade (15; 35) connected to the side surface of the hub with an outer edge (E1; E2; E2') of the inner peripheral blade (15; 35) that is extended from the side surface toward the outer edge side of the blade and positioned on the positive pressure surface, the inner peripheral blade includes a plurality of blade elements (15a, 15b; 35a, 35b), which are arranged side by side in the rotation direction of the blade, and the plurality of blade elements (15a, 15b; 35a, 35b) includes a first blade element (15a; 35a), which is arranged on the front edge (12-F) side in the rotation direction of the blade, and a second blade element (15b; 35b), which is arranged to be adjacent to the first blade element (15a; 35a) on a rear edge (12-R) side in the rotation direction of the blade, characterized in that a first opening (16; 36), which passes through the blade surface part from a negative pressure side toward the positive pressure side, is provided between the first blade element (15a; 35a) and the second blade element (15b; 35b) on the blade surface part, and the first blade element (15a; 35a) satisfies H/L ≥ 0.1 where L is a length of the straight reference line of the first blade element (15a; 35a) and H is a maximum value of a distance between the straight reference line and the front edge (15a-F; 35a-F) of the first blade element (15a; 35a). a hub including a side surface around a center axis; and a plurality of blades disposed on the side surface of the hub, wherein the blades each include a blade surface part extended from a base end connected to the side surface of the hub to an outer edge, and the blade surface part includes an inner peripheral part positioned on the base end side and an outer peripheral part positioned on the outer edge side, an inner peripheral blade (15; 35), which extends from the side surface of the hub toward the outer edge side, is formed on a positive pressure surface of the blade surface part at the inner peripheral part of each of the blades, the inner peripheral blade (15; 35) projects from the positive pressure surface of the blade surface part toward a positive pressure side, and includes a front edge (15a-F; 35a-F) in a rotation direction of the inner peripheral blade (15; 35) that is formed in a curved shape to be separated from a straight reference line toward a front edge (12-F) side in a rotation direction of the blade, the straight reference line connecting a lower end (E3; E4) positioned on the positive pressure surface at the base end of the inner peripheral blade (15; 35) connected to the side surface of the hub with an outer edge (E1; E2; E2') of the inner peripheral blade (15; 35) that is extended from the side surface toward the outer edge side of the blade and positioned on the positive pressure surface, the inner peripheral blade includes a plurality of blade elements (15a, 15b; 35a, 35b), which are arranged side by side in the rotation direction of the blade, and the plurality of blade elements (15a, 15b; 35a, 35b) includes a first blade element (15a; 35a), which is arranged on the front edge (12-F) side in the rotation direction of the blade, and a second blade element (15b; 35b), which is arranged to be adjacent to the first blade element (15a; 35a) on a rear edge (12-R) side in the rotation direction of the blade, characterized in that a first opening (16; 36), which passes through the blade surface part from a negative pressure side toward the positive pressure side, is provided between the first blade element (15a; 35a) and the second blade element (15b; 35b) on the blade surface part, and the first blade element (15a; 35a) satisfies H/L ≥ 0.1 where L is a length of the straight reference line of the first blade element (15a; 35a) and H is a maximum value of a distance between the straight reference line and the front edge (15a-F; 35a-F) of the first blade element (15a; 35a).