Owing to its high sensitivity and repeatability， optical interferometry is often used to measure geometric quantities， such as micro-displacement， with high accuracy. To achieve the accurate measurement of nanodisplacements， a linear relationship between the rotation angle of a petal-like interferogram and the displacement， was established and verified based on the interference of vortex beams and plane waves. A novel method of microdisplacement measurement was proposed， which used the structure of an interference system with vortex beams. The feasibility of the principle was verified by simulation， and a displacement experimental system was established for the measurement experiments. The experimental results show that when the displacement is 200.0 nm， the measurement result is 196.3 nm， with an error of 3.7 nm or 1.9%， which can achieve microdisplacement measurement on a nanometer scale. Compared with traditional displacement measurement schemes， such as spherical wave interference and conjugate vortex beams interference， the proposed method has significant advantages in measurement reliability and accuracy.