In 2019, renewable energies counted for 11,7% of primary energy consumption in France, behind nuclear power (40%), petroleum products (29%) and natural gas (16%). The production of renewable energies reaches 320 TWh in 2019, only 0,2% of which comes from renewable marine energies. What about renewable marine energies and the social acceptance of their development in France and specifically in the Gulf of Morbihan site (GM) in Brittany? This paper aims at providing empirical data for the deliberation of Tidal Current Turbines (TCTs) Energy development and its perception and acceptance by the GM residents and users. A survey aiming to reveal some understanding about the extent of knowledge and awareness related with renewable energy in general and the development of TCTs in particular was designed and realized. Around 727 participants spread over the 20 municipalities of the GM and representing all the socio-economic activities in this basin responded to an online survey and / or direct individual interview for 13 weeks from May to July, 2017. The overall outcome of the conducted survey indicates that TCTs is not a technology known by the majority of the population, their answers and remarks highlight the need to communicate about the TCTs project and about the technology itself. Although 55,9% of those surveyed gave a favorable opinion for the development of a TCTs project in the GM, the citizens interviewed requested to be actors in this project and to be informed in full "transparency" of the stages of the project's development. Keywords - Gulf of Morbihan (GM), Tidal energy potential, Perceptions of Tidal Current Turbines (TCTs), Favourable.