Abstract: Large vortices with scales ranging from hundreds meters to tens of kilometers are generally found in the atmospheric convective boundary layer (CBL). These vortices play important roles in the vertical transport of momentum, heat, water vapor and other tracers in the boundary layer. On the basis of the view of interaction between the convection in CBL and the gravity waves in the upperstable layer the author developed a convection-wave theory on the formation of large vortices. A ccording to the theory the wave number spectrum of the large vortices mainly depends on the atmospheric conditions in both of the upper and lower layers, such as wind speed, wind direction shear, stratification as well as temperature jump.