Coastal marshes are interface habitats between land and sea, with high biological productivity that provide many ecological functions and ecosystem services. Recent management trend has been oriented towards the restoration of these wetlands for ecological purposes. This study aimed to assess the short-term effect of restoration work - fostering river flow, water level management and bird roosting - involving the restructuring of a freshwater urban marsh and its partial reconnection to the coastal sea on fish community. Fish were inventoried before works and reconnection (in autumn 2019 and spring 2020) and after (seasonally in 2021) at two different stations: the East station drained by the Moulinette river whose bed was restored and the West station, restored and periodically reconnected to the sea to keep constant water levels in pounds. The changes in fish communities was studied through inter-comparison of taxonomic and functional structures using diversity indices. Results showed that works induced a shift in the fish assemblage composition with species replacement, without causing any erosion neither of its taxonomic or of its functional diversity. Contrarily, the reconnections to sea impacted both taxonomic and functional fish communities due to abiotic changes and immigration of estuarine and marine species. This study will (i) provide knowledge on the short-term resilience of fish community after the habitat restructuring in the restoration context, and (ii) give insights into management aims regarding the ecological functions of habitats targeted for restoration.