Disclosed are fixed reflector cross bar adjusting screws of a michelson interferometer. Screw head portions of fixed reflector adjusting screws are respectively processed with circular holes which have diameters of 1 millimeter. The circular holes are perpendicular to the axes of the fixed reflector adjusting screws. Cross bars which are 0.8 millimeters in diameter and 30 to 40 millimeters in length respectively penetrate through the circular holes. The both ends of the cross bars are processed to be enlarged or wrapped by adhesive tapes so that the cross bars are made to be not easy to drop. An original horizontal pull bar screw and an original vertical pull bar screw used for fine-tuning of the circle center position are completely abundant. In the experiment process, an original operation mode is completely followed when the overlapping of light spots is adjusted; and when the position of an equal inclination interference fringe circle center is adjusted, the position of the circle center can be stably and accurately adjusted simply by slightly rotating the cross bars to drive the fixed reflector adjusting screws to rotate.