Compared to circular shields, rectangular pipe jacking machine has many advantages such as high space utilization ratio and low construction cost. In the paper, a 3dimensional model is established for the shell of a large crosssection rectangular pipe jacking machine, the stress model of the shell is analyzed and founded, the modeling, constraint fixing and load determination of the shell are simplified by means of SolidWorks, and a design, verification and optimization method for the shell based on SolidWorks modeling is formed. The paper can provide reference for the design of the shells of other rectangular pipe jacking machines.