Biodiesel (BD) is often regarded as a carbon-neutral fuel. Many countries are investing resources in biodiesel technology development to respond to the need to improve energy sustainability and the threat of climate change. Since 2009, the South Korean Government has invested a considerable amount of money in developing marine BD (MBD) technology that converts carbon dioxide into diesel using marine microalgae cultivated in large quantities with the help of waste heat from nuclear power plants and/or coal-fired power plants. If the development is successful, 4800 tons of MBD a year, approximately 1820 cars fully fueled annually, will be produced from 2019. Furthermore, the South Korean Government is expected to continue to invest in MBD to improve the market share after 2019. Quantitative information about the public value of MBD technology development is widely demanded by the Government. This study aims to investigate the public value of MBD technology, the attributes of which it considers to be the reduction of greenhouse gas emissions, the mitigation of air pollutant emissions, new job creation, and the improvement of energy security. A choice experiment (CE) survey of 600 people was conducted during July 2016. The trade-offs among the attributes and the price were evaluated in the survey. The CE data were examined through a multinomial logit model. The marginal values for a 1%p reduction of greenhouse gas emissions, 1%p mitigation of air pollutant emissions, the creation of 100 new jobs, and an improvement of energy security caused by MBD technology development are computed to be KRW 1082.7 (USD 0.9), 918.1 (0.8), and 258.3 (0.2) per household per month, respectively.