Saccharina japonica is one of the most economically important seaweeds in China. Because of both internal and external forces, S. japonica farming in offshore waters has begun to emerge in China. Focusing on offshore aquaculture of S. japonica, this paper contains a discussion of the definition of inshore and offshore aquaculture of S. japonica, compares the advantages and disadvantages of these two aquaculture methods, and analyzes the driving forces of S. japonica offshore aquaculture. We also summarized the current situation and problems involved in S. japonica offshore aquaculture and proposed the development of a strategy, with the hopes that the discussion herein will provide new ideas and concepts for the healthy and sustainable development of S. japonica offshore aquaculture.