Inorder to analyze the dynamic mechanism of unusual activities of the subtropical high, based on the heat force and the whorlmovement dissipation effect, the partial differential vortex equations were space-time variable separated by Galerkin methods. Aiming at the subjective and man-made conven tionalmethod of choice in the space-based function, the research ideas of the EOF and the genetic algorithm combined inversion of the space-based functions from the actual sequence of fields were putforward. Agroup of trigonometric functions were chosen as a broad-space based function, with the leas-tsquares of the error of the based function and EOF typical fields, as well as the complete orthogonal conformation of based functions as the dualbound function. Then, the genet ic algorithm w as introduced to carry out the surface fitting and coefficientop timization of the based function, as aresul't the objective and reasonable constant differen tial equation of the subtropical high was obtained by inversion. Finally, based on the obtained nonlinear dynamics model the dynamic behavior and mechanism of the sub tropical high was analyzed and discussed under the in fluence of heat force. It is found that solar radiation heating and zonal differences in land and seamipacting the potential field and flow field changes of the sub-tropical areas are the miportant factors that canlead to the strength changes of the subtropical high and medium-term advance and retreat activities. The frontis gradual change, while the lastmore putup the characteristic of the break. Some meaning fulresults were gotthrough the analysis.