The mechanical properties and failure modes of lattice framed anchor system in preventing landslide are investigated through large-scale physical model test on the interaction between anchor system and landslide. The resistance of soil under lattice girder, the internal forces, displacements and deformations of lattice girder are obtained. Results show that under the actions of landslide thrust and anchorage force, the lattice girder as a whole is subjected to forces in an “S” shape, which means that the beam part below node was subjected to tension, the above node compression, and below mid-span of the beam compression, and above mid-span tension; with the increase of load and the gradual destruction of landslide model, the node of lattice girder bends towards the inside of the slope, the mid-span bends towards the outside. Moreover, the failure modes of lattice framed anchor system are summarized into four types bending failure in an “S” shape in the mid-span, cataclastic failure of node caused by compression, extrusion of soil between girders, and extrusion of soil above girders, among which plastic bending failure is a main failure mode.