In the construction of pile foundation at the Panzhou Station of the Shanghai-Kunming Railway, the rotary drill rig was used to dry-drill the holes, and dissolved caves were encountered in drilling of nearly 1/3 the foundation piles. Based on the analysis of different adverse situations, and according to the geological conditions of unfilled and semi-filled karst caves encountered, specific technical measures were adopted, including wall construction by backfilling soil and stone and compaction by reverse rotation, sinking boreholes section by section by squeezing plain concrete, protection of borehole walls and retaining of pile concrete with casing, leveling of uneven rock surface and re-drilling, point-backfilling and cementation; as a result, the pile foundation was successfully completed.