Abstract: The physical properties of the symmetric and antisymmetric motion,such as the conservation of the absolute angular momentum,the mutual conversions between various forms of energy,have been analysed by using the sets of equalions in p-coordinates controlling the motions in the primitive equation model atmosphere.The results show that only the symmetric part of zonal geopotential difference caused by orography and that part of the zonal frictional torque,have contribution to the change of the global absolute angular momentum,and that the mutual conversions between various forms of energy,in addition to those similar to the results in the classical case,include those associated with the symmetric and antisymmetric motion.