Abstract: In order to ascertain the effect of loess gulch on the bearing capacity of bridge pile foundation, for the first time, based on the self-developed platform model test, the model tests can fully reflect the characteristics and work performance of pile foundation in loess gulch area. The change rules of vertical bearing capacity, pile axial force and lateral friction force of the pile foundation with different slopes and pile lengths are analyzed, and some engineering technical advices are given based on test results. The results show that: (1) With the increase of slope, the bearing capacity of piles with the same pile length decreases, the influence degree of bearing capacity increases gradually, and the range varies from 7% to 35%. (2) The pile bearing capacity increases with the increase of pile length to some extent; when the pile length increases to a certain length, the rate of increase becomes slow. (3) The effective pile length with the same buried depth decreases with the increase of slope. (4) The design of bridge pile foundation should fully consider the engineering technology of preventing the soil around piles being eroded in the loess gulch area.