共建“一带一路”为海洋经济高质量发展创造了新机遇,为推动海洋产业结构优化升级带来了新动能。本文基于2007年—2018年我国11个沿海省市面板数据,运用面板固定效应模型、双重差分模型、倾向得分匹配+双重差分模型以及中介效应模型,实证检验了共建“一带一路”对海洋产业结构升级的影响效果和作用机制。研究发现：（1）共建“一带一路”能够持续显著促进海洋产业结构升级;（2）共建“一带一路”通过鼓励对外直接投资、提升科技创新水平实现海洋产业结构优化升级的中介效应显著;（3）共建“一带一路”促进海洋产业结构升级的效果具有异质性,在海洋经济相对发达的省市表现出更强的影响效果。今后应持续依托共建“一带一路”深化对外开放,加强政府间交流合作,消除投资壁垒,重点发展海洋科技,提高技术的市场转化率,从而更好地推动海洋产业结构优化升级。

Jointly building the Belt and Road has created new opportunities for the high-quality development of the marine economy and created new driving forces for the optimization and upgrading of the marine industry structure. Based on the panel data of 11 coastal provinces and cities in China from 2007 to 2018, this paper empirically tested the effect and mechanism of the Belt and Road Initiative on the upgrading of Marine industrial structure by using panel fixed model, DID model, propensity score matching + DID model and mediating effect model. The findings are as follows: (1) jointly building the Belt and Road can significantly promote the upgrading of marine industrial structure; (2) jointly building the Belt and Road has a significant mediating effect on the optimization and upgrading of domestic Marine industry structure by encouraging foreign direct investment and improving the level of scientific and technological innovation; (3) the effect of jointly building the Belt and Road Initiative on the upgrading of Marine industrial structure is heterogeneous. Provinces and cities with relatively developed Marine economy have a stronger impact than those with a lower level of Marine economy. In order to better promote the optimization and upgrading of the marine industry structure, it is of great necessity to continue to rely on jointly building the Belt and Road to deepen the reform and opening up, to strengthen inter-governmental exchanges and cooperation, to remove investment barriers, to focus on developing marine science and technology to improve the market conversion rate of technology.