The utility model, which belongs to the measurement technology field, relates to a butted rotor coaxiality alignment apparatus, thereby solving a problem of rotor centering alignment of large high-speed rotating equipment. The technical scheme of the apparatus is characterized in that the apparatus comprises a flange plate, a seamless tube, dial indicators and a dial indicator support seat. One end of the seamless tube is coaxially connected with the flange plate and the other end thereof is fixedly connected with the indicator support seat; and the dial indicators are fixed on the dial indicator support seat. According to the utility model, because the dial indicators are fixed on a rotor by the dial indicator support seat, the seamless tube and the flange plate and thus the distance between the dial indicators and another rotor is reduced, the measuring rods of the dial indicators can be directly pressed against the backrest wheel of the rotor, so that a problem of coaxiality alignment during the far-distance butting of two rotors can be solved. Moreover, the provided apparatus has advantages of simple structure, fast alignment speed, high precision, and reliable work and is especially suitable for rotor centering and alignment of large high-speed rotating equipment.