Abstract: Using a generalized beta-plane approximation f =fo+βoy －(δ0 /2)y2 , a kind of the solitary Rossby waves excited by theδ0 term excluding effects of shearing basic flow and topography et al is mainly investigated. The computational results show that the obtained solitary Rossby wave with meridional wavenumber 1 has a dipole structure with a high pressure in the north and a low in the south, which mainly exists in the weak westerly wind. On the other hand, the energy of dipole easily accumulates with the latitude. Thus, the beta parameter with the change of latitude may be one reason of producing dipole blocking in the mid-high latitudes.