Abstract: Wheel loader is a kind of heavy machinery and equipment, which is mainly used in the construction of construction projects, and it is the main auxiliary tool for building materials. At present, the widest application range is the reversal six-bar mechanism. Compared with other structures, this structure not only has better automatic flat-laying performance, but also has a large shoveling force and a more compact overall structure. This article analyzes the working device of the wheel loader, and the boom is the main research object, and analyzes the stress distribution of the working device of the boom.