Abstract: As an invasive species, Spartina alterniflora has widely spread along China's coastal areas, posing a severe threat to coastal ecological security. Due to its rapid expansion and strong adaptability to intertidal zones, it has become one of the most aggressive invasive plant species in China’s coastal ecosystems. The warm-temperate coastal region, as an essential economic, political, and cultural zone in China, plays a crucial role in national development. Maintaining the ecological stability of this region is therefore of great significance. Understanding the current distribution and potential spread of Spartina alterniflora is essential for implementing effective control strategies. This study utilized Sentinel-1/2 remote sensing images and the Google Earth Engine (GEE) platform to obtain the distribution points of Spartina alterniflora in the warm-temperate coastal region of China in 2023. Based on these data, along with 35 environmental variables, the MaxEnt model was employed to predict the potential distribution of Spartina alterniflora in the study area. The model achieved high classification accuracy, with an overall accuracy of 90.1% and a Kappa coefficient of 0.885. The results revealed that the total distribution area of Spartina alterniflora in the warm-temperate coastal zone of China in 2023 was approximately 74.83 km². Among the provinces, Shandong province exhibited the most extensive distribution, covering about 62 km². Jiangsu province and Hebei province followed with distribution areas of approximately 6.86 km² and 4.25 km², respectively, while Tianjin had the smallest distribution area at approximately 1.72 km². The suitability analysis categorized the study area into four zones: highly suitable (5.59%), moderately suitable (33.67%), lowly suitable (8.03%), and unsuitable (52.71%). The suitable regions were mainly concentrated in the southern part of Hebei Province, Tianjin, Shandong Province, Jiangsu Province, and the coastal mudflat regions of Dalian and Dandong in Liaoning Province. The key environmental variables influencing Spartina alterniflora growth were mean annual temperature (bio1), elevation (dem), soil type (soiltype), and precipitation in the wettest month (bio13). The optimal conditions for Spartina alterniflora growth in the warm-temperate coastal region include a mean annual temperature between 11.0 and 21.5 °C, low-lying coastal mudflat areas, coastal saline soil, and wettest-season precipitation ranging from 180-190 mm and 230-250 mm. The results indicate that Spartina alterniflora has a vast potential distribution area in the warm-temperate coastal region of China, with a notable trend of northward expansion. This continued spread poses a significant ecological threat by altering native wetland ecosystems, reducing biodiversity, and disrupting coastal hydrodynamics. If left unmanaged, the invasion of Spartina alterniflora could lead to severe degradation of wetland habitats and loss of ecosystem services. Therefore, it is critical to strengthen monitoring, prevention, and control measures to mitigate the invasion of Spartina alterniflora. Additionally, further research should focus on evaluating the effectiveness of different eradication strategies and assessing the long-term ecological impacts of its spread.