Abstract: The aerodynamic critical instability wind velocity of three-dimensional membrane structures is studied by combining the non-moment theory of thin shallow shells and the potential flow theory in fluid mechanics. The dynamic equilibrium equation of the structure is established using the non-moment theory of thin shells. It is assumed that the coming flow is ideal uniform potential flow. The aerodynamic interaction equations of the membrane structure are obtained for the wind in the arch or sag direction of the structure based on the aerodynamic force determined using potential flow theory and thin airfoils theory. The wind-structure interaction is taken into account in the equations. Bubnov-Galerkin approximate method is applied to transform the interaction equation into a second order linear ordinary differential equation; and Routh-Hurwitz stability criterion is used to determine the critical instability wind velocity. Finally, some important conclusions are obtained from parametric analysis.