A turbomolecular pump has multiple stages of alternately arranged rotors and stators. Each of the rotors has blades radially extending from a rotating body. Each of the stators has blades radially extending toward the rotating shaft of the rotating body. The blades provided on at least either of a rotor and a stator are formed in a twisted shape having a blade angle set by an expression in which the radial distance from the rotating shaft is a variable. The expression of the blade angle is composed of a first expression which provides the optimum angle of each blade on the outer side of a predetermined radius of the blade and also composed of a second expression which provides the blade angle suppressing, on the inner side of the predetermined radius, reverse flow of gas molecules.