The dataset consisting of 17 files compiles worldwide available nuclear gaseous 14C emissions (inorganic, organic and total) from 1950 to 2023. We use the European Commission RAdioactive Discharges Database (RADD, 2025) compiling the annual radioactive discharges of the European nuclear power plants (NPPs) and we include additional data sources, such as the Discharges of Radionuclides to the Atmosphere and the Aquatic Environment (DIRATA) database (IAEA, 2025) and institutional reports, in particular from the United Nations Committee on the Effects of Atomic Radiation (UNSCEAR) and the International Atomic Energy Agency (IAEA). Moreover, we consider publications and numerous annual plant-specific environmental reports providing 14C emission values for NPPs. In total, 14C emission values of nuclear facilities operating in Argentina, Bulgaria, Brazil, Canada, China, Czech Republic, Finland, France, Germany, Hungary, Japan, Lithuania, Romania, Slovakia, Slovenia, South Korea, Spain, Sweden, Switzerland, The Netherlands, United Kingdom, and the USA are presented. Beside annual 14C emissions, monthly, quarterly, and weekly values are also compiled for some nuclear facilities. If not otherwise mentioned, details about the data sources are available in the column Comments of the files.