In order to study the bearing characteristics of single loaded rock-socketed pile under horizontal load, pseudo-static model tests considering the vertical and horizontal loadings were adopted in view of the challenge of dynamic test, in which rock and pile are simulated with similar material. The elastic bending moment, rock pressure around the pile and the hysteresis curve of the pile top are analyzed under different slopes and elastic modulus of rock. The results show that the horizontal bearing capacity of pile foundation of rock slope is mainly related to shallow slope within the range of buried depth above 3D (D is pile diameter) . The failure pattern of the downslope rock mass is similar with that of the soil slope, which goes through three stages: the emergence of cracks, the development of failure surface and the failure of the shallow slope body, even though the upslope rock mass has not formed a complete failure surface. Finally, the shear failure of pile foundation leads to the failure of horizontal bearing capacity, indicating that when the slope is of rock, the slope mainly affects the positive bearing capacity. When the slope angle ranges from 15° to 30°, the positive bearing capacity increases by 41.3%, while the negative bearing capacity only increases by 0.15%. The slope material strength has an impact on both positive and negative bearing capacity. The pile-rock elastic modulus ratio changes from 2.8 to 0.9, while the positive and negative bearing capacity increase by 80.7% and 73.5%, respectively.