Abstract: Using TOVS data,corrected by variational method,into the numerical model's initial field over the Tibet an Plateau region where sparse observations exist,under the dynamical diag nosis,have investigated to minimize the larger error of initial fields in the numerical prediction model,which caused by the sparse observation on the Plateau,drafted the framework in which some bogus soundings are embodied with TOVS data over there in such a way that the dependability of the initial condition increases significantly.In the meantime,based on the dy namical diag nosis and analysis context,further confirmed that TOVS data are beneficial to improving the objectivity of initial fields,such as the characteristics of dynamical system,transportation channel of water vapor,and stratification stability over the Plateau.