This study utilized ERA5 reanalysis data and multiple observations to investigate the evolution of the remnants vortex of Typhoon Doksuri (2023) in the Northwest Pacific after it landfall, which caused significant damage in northern China. The main maintenance and recovery period were observed from the night of July 29th to the daytime of July 30th. The research revealed that during the maintenance of the remnant, it maintained a warm-core structure and was not influenced by dry and cold air. During the recovery process, a noticeable increase in water vapor convergence and moist potential vorticity was observed on the northeast side of the vortex center. Additionally, the northern movement of the remnant vortex was hindered by a zonal high-pressure belt, causing a reduction in its northward speed. Under the guidance of a mid-level high-pressure system, dry and cold air further intensified the temperature and moisture gradient between the mid-low-level remnant vortex and warm and moist air masses, resulting in a clear tilt of isentropic surfaces on the northern side of the vortex. This tilt in isentropic surfaces led to the vertical development of cyclonic vortex. Furthermore, during the sustaining and revival period, the remnant vortex continued to receive some heating from increased soil moisture. Additionally, significant latent heat release occurred due to radial moisture inflow and vertical upward motion on the northeast side of the remnant vortex. This release of latent heat provided the necessary conditions for the maintenance and strengthening of the remnant vortex.