The geomechanical model testing based on pile-soil interaction and structure model test of portal anti-sliding piles are conducted to study its stress mechanism. Strain gauges are pasted in internal of piles to discuss its stress features, and dial indicators are placed at key positions to analysis its displacement features. The results showed that the displacement of rear pile is larger than front pile, and the displacement of pile top is larger than the position of sliding surfaces. The stress distribution of rear pile and front pile both present the "s" distribution and the stress value of top rear pile and front pile is not null whose value increases with the growth of thrust load.