Abstract: A 50T hydraulic excavator connecting rod was taken as the research object. Creo5.0 was used to establish the three-dimensional digital model of two types of connecting rod structure, I - type and box - type, and combined with the Static Structural in ANSYS Workbench, the deformation and stress distribution of the two types of connecting rod structure under the maximum bucket digging force were analyzed. The results of deformation and stress show that the total deformation of box structure is much smaller than that of I - shape. The high stress area of the two types of structures is distributed in the weld position of the web/bending plate and the cylinder, and the maximum stress value of the I - structure is 19.2% higher than that of the box structure, and the highest stress value is located at the end of the weld, and the polishing treatment after surfacing is often used in the process of manufacturing.