Abstract: The telescopic arm is a commonly used working device on construction machinery, which drives the telescopic arm to perform telescopic and pitching movements through the extension and retraction of the telescopic cylinder and pitching cylinder, thereby achieving a larger operating radius and height. Taking a certain type of telescopic arm that adopts hydraulic control leveling as the analysis object, the Creo 3D software is used for 3D modeling, and theoretical calculation and finite element simulation are combined to calculate the stress, strain, and displacement of the telescopic arm under various extreme working conditions. The calculation results indicate that the selected structural material can meet the structural strength requirements of the telescopic arm, and the strain and displacement of the structure are small, which meets the design requirements. The analysis results provide a reference basis for the design of the structure.