| Professor Sanford Kadish FBA | Year of birth 1921 | Year of death 2014 | Year elected 1989 | Fellowship category Corresponding |
| Professor Dr Werner Kaegi FBA | Year of birth 1901 | Year of death 1979 | Year elected 1975 | Fellowship category Corresponding |
| Professor Paul Kahle FBA | Year of birth 1875 | Year of death 1964 | Year elected 1948 | Fellowship category UK |
| Lord Richard Kahn CBE, FBA | Year of birth 1905 | Year of death 1989 | Year elected 1960 | Fellowship category UK |
| Sir Otto Kahn-Freund QC, FBA | Year of birth 1900 | Year of death 1979 | Year elected 1965 | Fellowship category UK |
| Professor Daniel Kahneman FBA | Year of birth None | Year of death 2024 | Year elected 2008 | Fellowship category Corresponding |
| Rt Hon Lord Nicholas Kaldor FBA | Year of birth 1908 | Year of death 1986 | Year elected 1963 | Fellowship category UK |
| Professor Lech Kalinowski FBA | Year of birth 1920 | Year of death 2004 | Year elected 1992 | Fellowship category Corresponding |
| Professor George Kane FBA | Year of birth 1916 | Year of death 2008 | Year elected 1968 | Fellowship category UK |
| Professor Dr Richard Kannicht FBA | Year of birth 1931 | Year of death 2020 | Year elected 1993 | Fellowship category Corresponding |
| Revd Father Thomas Käppeli FBA | Year of birth 1900 | Year of death 1900 | Year elected 1974 | Fellowship category Corresponding |
| Professor Vassos Karageorghis FBA | Year of birth 1927 | Year of death 2021 | Year elected 1973 | Fellowship category Corresponding |
| Professor Bernhard Karlgren FBA | Year of birth 1889 | Year of death 1978 | Year elected 1968 | Fellowship category Corresponding |
| Professor Annette Karmiloff-Smith CBE, FBA, FMedSci | Year of birth 1938 | Year of death 2016 | Year elected 1993 | Fellowship category UK |
| Mrs Semni Karouzou FBA | Year of birth 1900 | Year of death 1995 | Year elected 1973 | Fellowship category Corresponding |
| Professor Dr Max Kaser FBA | Year of birth 1906 | Year of death 1997 | Year elected 1977 | Fellowship category Corresponding |