A multiblade blower, comprising: a casing having only one air inlet; and an impeller arranged in the casing so as to be rotatable, wherein the impeller comprises a main plate fixed to a drive shaft at the side opposite to the air inlet, and a plurality of centrifugal blades positioned so as to form a cylindrical shape, wherein: an intermediate support is arranged in an internal space of the plurality of centrifugal blades, the intermediate support is positioned between the main plate and the air inlet, and is supported by the drive shaft, the plurality of centrifugal blades are held by the intermediate support as well as being held by the main plate, the intermediate support comprises a plurality of connecting portions, the plurality of connecting portions extend radially outward from the drive shaft in a radial shape, the plurality of connecting portions each have a blade shape of an axial-flow fan, and assuming that the end point of the centrifugal blade on an inner peripheral side is referred to as a leading edge, a straight line crossing, at a right angle, a radial line passing through the rotation axis and the leading edge and extending toward a rear side in the rotation direction is referred to as an inner peripheral tangent line, a tangent line of the blade passing through the leading edge of the blade is referred to as a blade tangent line, and an angle formed by the blade tangent line and the inner peripheral tangent line is referred to as a blade inlet angle, the multiblade blower being characterized in that for each of the plurality of centrifugal blades the blade inlet angle in a region of the blade on a downstream side with respect to the intermediate support is set larger than the blade inlet angle in a region of the blade on an upstream side with respect to the intermediate support. a casing having only one air inlet; and an impeller arranged in the casing so as to be rotatable, wherein the impeller comprises a main plate fixed to a drive shaft at the side opposite to the air inlet, and a plurality of centrifugal blades positioned so as to form a cylindrical shape, wherein: an intermediate support is arranged in an internal space of the plurality of centrifugal blades, the intermediate support is positioned between the main plate and the air inlet, and is supported by the drive shaft, the plurality of centrifugal blades are held by the intermediate support as well as being held by the main plate, the intermediate support comprises a plurality of connecting portions, the plurality of connecting portions extend radially outward from the drive shaft in a radial shape, the plurality of connecting portions each have a blade shape of an axial-flow fan, and assuming that the end point of the centrifugal blade on an inner peripheral side is referred to as a leading edge, a straight line crossing, at a right angle, a radial line passing through the rotation axis and the leading edge and extending toward a rear side in the rotation direction is referred to as an inner peripheral tangent line, a tangent line of the blade passing through the leading edge of the blade is referred to as a blade tangent line, and an angle formed by the blade tangent line and the inner peripheral tangent line is referred to as a blade inlet angle, the multiblade blower being characterized in that for each of the plurality of centrifugal blades the blade inlet angle in a region of the blade on a downstream side with respect to the intermediate support is set larger than the blade inlet angle in a region of the blade on an upstream side with respect to the intermediate support. an intermediate support is arranged in an internal space of the plurality of centrifugal blades, the intermediate support is positioned between the main plate and the air inlet, and is supported by the drive shaft, the plurality of centrifugal blades are held by the intermediate support as well as being held by the main plate, the intermediate support comprises a plurality of connecting portions, the plurality of connecting portions extend radially outward from the drive shaft in a radial shape, the plurality of connecting portions each have a blade shape of an axial-flow fan, and assuming that the end point of the centrifugal blade on an inner peripheral side is referred to as a leading edge, a straight line crossing, at a right angle, a radial line passing through the rotation axis and the leading edge and extending toward a rear side in the rotation direction is referred to as an inner peripheral tangent line, a tangent line of the blade passing through the leading edge of the blade is referred to as a blade tangent line, and an angle formed by the blade tangent line and the inner peripheral tangent line is referred to as a blade inlet angle, the multiblade blower being characterized in that for each of the plurality of centrifugal blades the blade inlet angle in a region of the blade on a downstream side with respect to the intermediate support is set larger than the blade inlet angle in a region of the blade on an upstream side with respect to the intermediate support.