Abstract: In the context of global climate change, sandy coastlines of islands are widely subject to different degrees of erosion. Human activities have become a primary driver force affecting the stability of island coastlines. Effectively identifying the key factors influencing the evolutionary pattern of island coastlines holds significant importance for coastline protection. Based on the data including 1964 digital topography map, 11 phases of historical remote sensing images during 1984-2022, and measured coastline and surrounding bathymetric data in 2016 and 2022, discussed the dynamic changes in coastline, erosion-deposition pattern of sandy beaches, and their driving factors on Ma Island, Hainan. The results show that typical human activities such as channel excavation and pier construction have significantly altered the stability of the island’s coastlines over the past 60 years. The southern and northern coastlines advanced seaward by 0.10 km and 0.06 km, respectively, while the total coastline length increased from 5.24 km to 8.29 km, with a growth rate of 0.053 km/a. The area of the island expanded from 55.70 hm² to 87.72 hm², at a rate of 0.552 hm²/a. The northern coastline experienced weak erosion, with scouring depths less than 1 m, whereas the southern coastline remained in dynamic equilibrium, with topographic changes ranging between −1 m to 1 m. Typical human activities have notably disruped the natural evolution of the coastlines. The seabed near the northeastern area of the Ma Island has accumulated sediment with an average deposition depth of approximately 1 m, with a maximum of 3 m near the proposed bridge site. Due to these topographic changes, water depths in the eastern disconnected area of the island increased by 3-6 m compared to pre-excavation conditions. The findings of this study provide a scientific basis for the protection and sustainable development of islands coastlines.