Abstract: In view of the problems of low measurement dimension, large error and easy to be affected by dust in current straightness measurement method of hydraulic support, a straightness measurement method of hydraulic support based on inter supports walking robot was proposed. This measurement method is mainly used to chock-shield hydraulic support, sensors are arranged on the inter supports walking robot, which is used for directly measuring multi-dimensional position offset information such as transverse offset, longitudinal offset, transverse bevel angle and longitudinal dip angle of hydraulic support base, then the straightness information of the hydraulic support is indicated by the support position offset. The experimental results show that the deviation error of the two adjacent supports is within 0.2 cm and the angle error of the two adjacent supports is within 10′. When the experimental supports model increased to 100 units, the accumulative error of position offset is expected to 10 cm, angle cumulative error is 8°20′ according to center distance of 1.5 m for conventional hydraulic support on the working face length of 150 m. For length of fully mechanized working face is less than 150 m, the accumulated error is in the acceptable range, can meet measurement demand of hydraulic support straightness. Compared with the traditional one-dimensional measurement information, the method can provide more detailed reference for the control of hydraulic support group through the four-dimensional position offset information.