Abstract: walnut shelling is the first step in walnut processing, must first resolve. As the walnut species complex, irregular in shape, size differences between large, small shell kernel space, the shell deformation of a complete breakdown of the required volume in the shell kernel space, so shelling take Jen difficult. Walnut sheller is to remove the walnut shell and pods of field operations by walnut machine. As the walnut their physiological characteristics and walnut walnut shelling the field can not be joint operations with the harvest, but only the water content in the walnut pods dropped only after a certain level of shelling. With the continuous development of planting walnut, walnut shelling by hand have failed to meet high production demands, the implementation of shelling mechanization imminent. In this paper, the sheller is extruded walnut sheller, mainly by feeding hopper, active roll, roll, and a gate passive etc.. In this paper the extrusion of the shelling device shaft and bearing design calculations. With the development of computer, the modern mechanical design also appears to diversify the use of advanced CAD / CAE tools to conduct research on the mechanical system has become a trend. Pro / ENGINEER is a CAD / CAM / CAE in one of the major design software. This paper finite element analysis to be carried out mainly in the following research steps: 1, a finite element model and the applied load with the Pro / E software to draw a simple chart breaking shell device, connected to the load imposed by the finite element model, its advantages is: ① load can be directly applied to the master node, and therefore simplify the analysis, generally not a problem; ② simply Xuanze all the required nodes, and directly specify the constraints. 2, the basic stress analysis in finite element analysis to establish the required geometry, materials, constraints, and load boundary conditions, we must build on top of the model of the basic stress analysis. 3, run the model sensitivity analysis sensitivity analysis of the main research is to study the specific parameters of the model characteristics of the situation, that of model-specific changes in the sensitivity level for the parameters. 4, optimal design of optimal design analysis to ensure that the stress model does not exceed a certain minimum ratings and costs (the consumption of materials, at least, that the quality of the lightest), which is an optimization problem. Using Pro / ENGINEER software build broken shell body and the geometric model of finite element analysis. Because Pro / ENGINEER has strong parametric functions, Pro / MECHANICA on the use of parametric tools to the advantage of the geometric model sensitivity analysis and optimal design, which is Pro / MECHANICA difference other finite element software the most striking feature of the final reasonable mechanical dimensions, complete the design. Keywords: walnut shelling, finite element stress analysis.