A centrifugal fan, comprising: an impeller rotating around a rotation axis; and a bell mouth guiding air to the impeller , the impeller including a shroud provided to have a gap between the shroud and an end of the bell mouth in a circumferential direction, and a plurality of blades arranged along a circumferential direction of the shroud , and assembled to the shroud , wherein in a blade cross section passing a front edge of the blade and a rear edge of the blade, when an angle (β) between a tangential line (L1) to a camber line (CL) at an intersection point (P) of the camber line (CL) and an arc around the rotation axis, and a tangential line (L2) to the arc at the intersection point (P) is defined as a blade angle (β), characterized in that : the blade has at least one of a decreasing shape and a fixed shape, the decreasing shape being such that the blade angle (β) decreases as the intersection point (P) is shifted toward the rear edge side on the camber line in a portion of the front edge side in the blade cross section of the shroud side, and the fixed shape being such that the blade angle (β) is fixed even if the intersection point (P) is shifted toward the rear edge side on the camber line in a portion of the front edge side in the blade cross section of the shroud side. an impeller rotating around a rotation axis; and a bell mouth guiding air to the impeller , the impeller including a shroud provided to have a gap between the shroud and an end of the bell mouth in a circumferential direction, and a plurality of blades arranged along a circumferential direction of the shroud , and assembled to the shroud , wherein a shroud provided to have a gap between the shroud and an end of the bell mouth in a circumferential direction, and a plurality of blades arranged along a circumferential direction of the shroud , and assembled to the shroud , wherein in a blade cross section passing a front edge of the blade and a rear edge of the blade, when an angle (β) between a tangential line (L1) to a camber line (CL) at an intersection point (P) of the camber line (CL) and an arc around the rotation axis, and a tangential line (L2) to the arc at the intersection point (P) is defined as a blade angle (β), characterized in that : the blade has at least one of a decreasing shape and a fixed shape, the decreasing shape being such that the blade angle (β) decreases as the intersection point (P) is shifted toward the rear edge side on the camber line in a portion of the front edge side in the blade cross section of the shroud side, and the fixed shape being such that the blade angle (β) is fixed even if the intersection point (P) is shifted toward the rear edge side on the camber line in a portion of the front edge side in the blade cross section of the shroud side. the blade has at least one of a decreasing shape and a fixed shape, the decreasing shape being such that the blade angle (β) decreases as the intersection point (P) is shifted toward the rear edge side on the camber line in a portion of the front edge side in the blade cross section of the shroud side, and the fixed shape being such that the blade angle (β) is fixed even if the intersection point (P) is shifted toward the rear edge side on the camber line in a portion of the front edge side in the blade cross section of the shroud side. <EOS>