The invention discloses a design and calculation method of a zero bending moment shield tunnel cross section. In the method, overall buried depth conditions, surrounding water and soil mechanical properties, underground water level conditions and the like of the top of a shield tunnel are analyzed according to formation conditions of the shield tunnel, the designed water and soil pressure mode of the shield tunnel is determined after comprehensive analysis, in this way, the rational axis and key parameters of shield tunnel cross section are designed, the cross section of the shield tunnel is of an egg-shaped structure which is small in the top and big in bottom, and the cross section theoretical bending moment of the shield tunnel cross section is zero under the effect of the designed water and soil pressure. The design and calculation method of the zero bending moment shield tunnel cross section has the advantages that the design and calculation method is simple and easy to operate, compared with a traditional shield tunnel, on the condition that the project cost is not basically increased, the bending moment of the designed zero bending moment shield tunnel is reduced to the greatest extent, therefore the cross section deformation of the shield tunnel and the expansion deformation of a pipe sheet longitudinal joint connector are avoided, breakage and water seepage of the pipe sheet longitudinal joint connector are prevented, and the using quantity of steel bars in a pipe sheet is reduced.