Aiming at the problem of insufficient research on the deformation characteristics of the pile foundation of the excavation near the pile-plank subgrade，the deformation control of the pile-plate structure pile foundation by the excavation of the foundation pit was studied based on a deep foundation pit project of Shanghai Airport Line. The finite element method was used to analyze the deformation law of the roadbed. Based on the deformation of the pile foundation，the influence zoning was carried out，and a method for calculating the allowable limit value of the deformation of the envelope structure based on the pile deformation control was proposed. The research results show that：The horizontal displacement curve of the pile foundation near the foundation pit is arched，the horizontal displacement of the entire pile body is large，and the maximum horizontal displacement of the pile foundation is 5.66 mm. The horizontal displacement curve of the pile foundation far away from the foundation pit is cantilever-shaped，and the maximum horizontal displacement occurs at the top of the pile，and the horizontal displacement of the deep pile is small. The affected area of pile foundation deformation under excavation depths of 9.5，17.4 m，and 25.5 m is divided into Zone A (danger zone)，Zone B (warning zone)，and Zone C (safety zone)，and engineering protection measures are proposed for each zone. A method for calculating the allowable limit of the deformation of the envelope structure under the control of pile foundation deformation is proposed in accordance with Technical Code For Foundation Pit Engineering.