Offshore renewable energy has been developed as an important source of clean energy for achieving sustainable development and tackling climate change. Whilst the generation of energy from the water, current and wind is mentioned in the Law of the Sea (LOS) Convention, this technology was in its infancy at the time when the Convention was drafted and therefore various challenges arising from offshore renewable energy activities were not foreseen. This thesis examines the manner in which and the extent to which the LOS Convention reinforces the regulation of offshore renewable energy activities. In doing so, it considers the relationship between the LOS Convention and subsequent instruments addressing offshore renewable energy activities with a view to determining the ways in which the LOS Convention is able to respond to the emergence of new uses of the marine environment. The development of the law of the sea is a process of compromise between the rights of the coastal States in relation to their maritime zones on the one hand and the interests of other States in the lawful uses of the oceans on the other hand. Whilst the LOS Convention was adopted in order to establish a stable legal framework governing all uses of the oceans, the Convention provides a certain degree of flexibility to accommodate new developments in the oceans. Legal mechanisms, including rules of reference, regional rules, treaty interpretation and soft law, can be used to elaborate the regulation of offshore renewable energy activities while maintaining the balance of interests between the coastal State and other States. The thesis explores the different issues raised by the regulation of offshore renewable energy activities, including environmental impact assessment, environmental regulation from operations, safety of navigation, and decommissioning. Each chapter highlights different mechanisms to elaborate on relevant provisions of the LOS Convention. In addition, the last chapter of the thesis discusses marine spatial planning as a policy tool for integrated oceans management to deal with the issues arising from offshore renewable energy activities in a comprehensive manner. The thesis indicates that the LOS Convention is a living instrument, which evolves to adapt to new challenges arising from offshore renewable energy activities through different legal mechanisms. The LOS Convention provides an adequate legal framework to interact, incorporate and supplement with other legal instruments in the regulation of offshore renewable energy activities.