As the ecological heart of the Xiongan New Area, the protection of Lake Baiyangdian Wetland water environment has been a priority. Various measures have been implemented, including water transfers from upstream reservoirs, supplementation via the South-to-North Water Diversion Projects middle route, and the Yellow River Diversion to Baiyangdian, creating a new pattern of multi-source water supply. These efforts have significantly improved the overall condition of the water environment. However, due to the long-term impacts of intensive human activities and the complex and varied topography of the region, Lake Baiyangdian Wetland still faces challenges such as poor water circulation in certain areas and seasonal. Therefore, understanding the characteristics and patterns of water renewal cycle and pollutant transport is crucial for the effective management of Lake Baiyangdian Wetland water environment. This study constructed a hydrodynamic model of Lake Baiyangdian Wetland using measured data to simulate water renewal cycle and tracer transport time across different seasons. The temporal and spatial distribution differences were analyzed to reveal the characteristics and patterns of water renewal and pollutant transport in Baiyangdian Wetland. The results indicated that there were significant spatial and temporal variations in water renewal cycle. Spatially, the water renewal cycle in the northeastern and southwestern regions of Lake Baiyangdian Wetland exceed 300 days, while most areas in the central region had renewal cycles longer than 200 days. The southern and southeastern regions maintain renewal cycles between 100 and 200 days, whereas river inlets and channels exhibit renewal cycle of less than 50 days. Temporally, the areas with renewal cycles exceeding 300 days were smallest in summer and autumn, accounting for less than 3% of the total area, while areas with renewal cycles under 200 days were largest, accounting for more than 65%, indicating better overall renewal capacity in these seasons compared to winter and spring. Similarly, there were considerable spatial and temporal variations in tracer transport times. The longest tracer transport times occur at the Xiaoyi River in the southern region and the Yellow River Diversion to Baiyangdian inlet, with average times of 310 days and 275 days, respectively. In contrast, the shortest transport times were observed at the Baigou River inlet in the north and the Fu River inlet in the west, with averages of 240 days and 202 days, respectively. Temporally, tracer transport times in Lake Baiyangdian Wetland were significantly shorter in summer and autumn than in spring and winter, reflecting faster water movement and better exchange and circulation during these seasons. The findings of this study provide important scientific references for the management of Baiyangdian Wetland water environment and the restoration of its aquatic ecosystem.