Distributed Brillouin optical fiber sensor has great potential for slope monitoring. The sensing fiber is easy to be broken due to extensive local strain， and it is often difficult to obtain accurate measuring results due to the limitation of the spatial resolution. In order to fit for the slope monitoring， an Optical Fiber Sensing Structure（OFSS） for the distributed Brillouin optical fiber sensing network is developed. The OFSS composes of a PVC pipe and two pulleys， constructing multiple round-trips for the sensing fiber. The length of sensing fiber for a short spatial length is extended significantly. So both the sensing accuracy and the tolerance to local deformation of the fiber are improved effectively. A comparative calibration experiment is designed in the laboratory to verify its performance with the spatial resolution of 1 m. What's more， the effect of the proposed OFSS for landslide monitoring is confirmed through an on-site monitoring test on a shallow artificial slope. In addition， since the optical cable has no contact with the outside under the protection of the modified device， the survival rate of the cable is increased significantly.