With the increasingly severe climate change situation and the trend of green energy transformation, the development and utilization of hydrogen energy has attracted extensive attention from government, industry, and academia in the past few decades. Renewable energy electrolysis stands out as one of the most promising hydrogen production routes, enabling the storage of intermittent renewable energy power generation and supplying green fuel to various sectors. This article reviews the evolution and development of green hydrogen policies in the United States, the European Union, Japan, and China, and then summarizes the key technological progress of renewable energy electrolysis while introducing the progress of hydrogen production from wind and photovoltaic power generation. Furthermore, the environmental, social, and economic benefits of different hydrogen production routes are analyzed and compared. Finally, it provides a prospective analysis of the potential impact of renewable energy electrolysis on the global energy landscape and outlines key areas for future research and development.