Seagrasses like Posidonia oceanica provide a wide range of benefits for the ocean and for the planet. Efforts in conservation and restoration have increased in the last 20 years to preserve P. oceanica meadows; a plenty of works have been conducted to develop restoration and planting actions as a way to offset the regression of this seagrass in the Mediterranean Sea. We here compile the information on these studies to make a bibliographic review. The review results showed that seedlings grow better on dead matte and rock covered with algae in calm waters with moderate depths. We highlighted the gaps of knowledge on restoration actions of Posidonia oceanica. Furthermore, with intensive and integrative work these gaps could be filled in the upcoming years.