Abstract: In this article, using simplified hydrodynamic equations of barotropic nondivergent atmosphere in cylindrical coordinates, the nondispersion conical solulion of spiral planetary wave is discovered. The formula of wave speed and the diagnostician formula in relation to wave parameter are nearly conformed to observed facts. It might mean that the nondispersion conical wave realy exists in the atmosphere. At least it might be a close approximation to the actual nonlinear wave.