With the rapid development of computer hardware and software technology, CAD technology is widely used in the field of engineering technology, and various design software in different fields are constantly being introduced. Based on the analysis of the pile foundation design steps and key calculations in the design, this paper adopts the method of parametric design and drawing. The calculation results show that the foundation pile will not buckle under the vertical design load of the pile top, and the stability of the bridge foundation pile meets the design requirements. Subsequent inspection results showed that all indicators of the bridge pile foundation and superstructure met the requirements, and the bridge was operating well and no safety hazards were seen. The analysis of the influencing factors of the engineering example shows that there is a critical pier height for the pile-column bridge foundation pile in the steep slope section, which is related to the depth of the foundation pile; The depth ratio should not exceed 0.5. With the increase of the elastic modulus E of the pile, the critical buckling load of the foundation pile gradually increases, while the length of the calculated stability pile gradually decreases. With the increase of the pile diameter, the critical pier height value of the pile gradually decreases, and the ratio of the height of the pier to the depth of the foundation pile decreases with the increase of the pile diameter. When designing the foundation pile of a type bridge, a reasonable and effective selection of the diameter of the foundation pile plays an important role in improving its buckling stability.