The southwest vortex (SWV) has strong disasterability and extensive influence, which is of great significance to reveal its rainfall mechanism and climate characteristics. The objective identification algorithm based on grid data is one of the important basic contents in the research field of the SWV. The local disturbance caused by high spatial resolution grid data and the influence of topography on the integrity of SWV circulation are the main reasons for the low identification accuracy of existing algorithms. In this paper, a new objective identification method for the SWV based on 700hPa wind field is proposed. This method can overcome the adverse effects of local disturbance and terrain occlusion without pre-processing the identification data such as smoothing, and significantly improve the accuracy of the SWV center identification. The improved tracking algorithm can recognize the new SWV, avoid the wrong connection of the old and new SWV centers, and obtain more objective SWV tracks. The evaluation results show that the average identification hit rate, missing report rate and false alarm rate of the new method are 85.71%, 14.29% and 11.7%, respectively. In the area east of 104°E, which is less affected by terrain, the identification hit rate is more than 90%, and the missing report and false alarm rate are both lower than 10%. Better recognition effect and higher computational efficiency make the new method more satisfying to the needs of scientific research and professional work.