Taking an inverted well designed for Yixing City Rural Sewage Reconstruction Project as an example, the design idea of inverted well, the design concept of circular inverted well structure and the applicable principle of foundation pit height are specially expounded. The Von-Mises formula suitable for a circular well is derived. The analytical solution obtained by the formula is similar to the calculation result obtained by the finite element software. The comparison error is within 5%. This deduced formula can be used by the engineering technicians to analyze the stress of circular well.