Abstract: The impact of cold waves on residual sea level offshore Zhejiang is significant and cannot be overlooked. This studyfocuses on understanding the patterns and mechanisms behind changes in residual sea level in this region during strong cold waveevents. The research aims to provide insights into how cold waves affect coastal and estuarine processes. Additionally, the findingsare intended to support further studies on cold wave dynamics and contribute to disaster prevention and mitigation efforts. A highresolutionnumerical model is developed using ROMS for the Bohai Sea, Yellow Sea, and East China Sea, focusing on the ZhoushanIslands area with mesh refinement. The model is applied to study the response of a typical cold wave event in the Zhejiang adjacentseas during January 2016. By analyzing harmonic constants of multiple tidal stations and measured sea level data, the suitablecombination of wind field data, wind stress drag coefficient, and bottom friction coefficient for the study area is determined throughsensitivity numerical experiments. The simulation results effectively capture changes in residual sea level during the cold waveevent, as verified by observational data from coastal tidal gauges. The study revealed spatial variation patterns in residual sea levelsin the Zhejiang adjacent seas. Under the influence of cold waves, variation amplitudes reach up to 0.6 meters from Hangzhou Bay toZhoushan Islands. The spatiotemporal distribution of residual sea level during the cold wave transit period is significantlyinfluenced by cold wave wind speed, wind direction, and the complex terrain along the Zhejiang coast. The change in residual sealevel lags by approximately 1 day compared to the change in cold wave wind speed. Significant spatial variability is observed in theresponse of residual sea level to cold wave winds. Sea level fluctuations off Taizhou and Wenzhou show a strong correlationwith cold wave wind speed, with correlation coefficients exceeding 0.65. In contrast, Hangzhou Bay exhibits a negative correlationbetween wind speed and residual sea level, with correlation coefficients ranging from 0.53 to 0.65. Near the Zhoushan Islands,complex correlations between wind speed and residual sea level are also noted. The variation in residual sea level near the coastof Zhejiang Province is attributed to two main factors. These are Ekman transport induced by wind stress and Kelvin waves triggeredby the weakening of northerly winds.