Seagrass beds are important on ecological roles in the marine biodiversity. They are a breeding ground for some species, habitat for others and a feeding area for many species and very well known in the climate change mitigation. Previous studies show that the seagrass bed covers about 0.15% area of the coast of Madagascar, which is concentrated on the western part. However, these meadows are currently being degraded as a result of natural phenomenal and anthropic activities. Protection, conservation and restoration activities are the best ways to recover and manage sustainably the seagrass as blue Carbone ecosystem. For Madagascar, very limited literature exists for seagrass ecosystems as tools for decision makers. We need good scientific information for future management and Restoration of seagrass ecosystem, that the reason way of the present project entitled: Trial of seagrass restoration techniques in Ranobe Bay, southwest of Madagascar. The aim of this project is to find the best technique of restoration by testing three techniques for transplantation of seagrass. The identification of best parameters as factors involving on the growth of seagrass are primordial such as: nature of the sediment, physical and chemical parameters.