Tang, S. He, T. Li, M. Liao, R.Y. Ou, Z.N. Sheng, W.F. Tao, Y. Yu, H.H. Zhou, L. JACoW Publishing Geneva, Switzerland Positioning measurement is regraded as an effective way for the position compensation and feedback of nano-experimental apparatus. However, it usually suffers many restrictions from the complicated applied occasion of a typical performance beamline for next-generation synchrotron radiation light source. To deal with the problem, a compact direct measurement method based on grating interferometers is presented. The principle, configuration, experiment are designed and implemented for the verification of the feasibility. It performs a high resolution in orthogonal/lateral direction relative to laser beam, which can overcome an infeasible shortage of a typical interferometer for direct lateral positioning. So, it is used for positioning measurement & compensation between KB mirrors and nano-stages of a sample for the experiments of CDI, bragg-CDI, pytchograph, XPCS, etc. Compared with the existed methods, huge frame, two vacuum chambers restriction, multi-axis interferometer and benchmark relay are avoided for the compact system by using proposed method.