The article examines the goals and main directions of Spain’s sustainable development («green transition») for the period of up to 2050 in the context of climate changes. The key direction of this process is the energy transition to renewable energy sources (solar, wind energy, biofuels) which reduce the intensity of CO2 emissions and other greenhouse gases that pollute the environment, and increase energy efficiency, labor productivity, competitiveness and growth rates of the national economy. As a result of the transition to low-carbon fuels that began in the first decade of the century, Spain has achieved progressive results in reducing the intensity of greenhouse gas emissions, particularly noticeable in its energy sector. As for other ambitious tasks of the Spanish «green agenda» to decarbonizes industry, transport and the agricultural sector, they are still at the initial stage of solution, not to mention the closest connection of this process with other serious technological, financial and socio-economic problems of the country’ s future.