Abstract: The Zhuzikou delta，located on the east branch of the Ouchi River，has been one of the fastest-growing and largest marshlands in the Dongting Lake area over the past century. Based on the historical maps and aerospace remote sensing data from 20 periods since 1933，this paper analyzed the spatiotemporal evolution of the delta through remote sensing interpretation and historical comparative analysis. The results showed that over the past 90 years，the Zhuzikou delta had been persistently advancing towards the lake area，with the deposited high-level bottomland being reclaimed into embankments. The old river channels had been abandoned and evolved into inner lakes of a blocked river type within the embankments，while the new river channels had been continuously extended towards the lake area along changing paths caused by multiple course changes. The channels of the lower reaches in the Zhuzikou delta have extended 38.99 km towards the lake area at an average annual rate of 428.46 m/a. The sedimentation area in the delta has expanded to 340.19 km² at an average annual rate of 3.74 km²/a. Reclamation of the delta has been carried out in parallel with sedimentation，with a cumulatively reclaimed area of 230.42 km²，accounting for nearly 50% of the total sedimentation area. The expansion rate has been varying across periods，including a slow expansion period from 1933 to 1954，a rapid expansion period from 1954 to 1998，a period of relative stability from 1998 to 2010，and a slight shrinkage period from 2010 to 2024. The delta has started to shrink since 2010，marking an end of its expansion history since 1933. The research findings provide original data for the scientific protection and restoration of wetland resources in the Dongting Lake.