In 1956, after a final convalescent period in the French Alps, Joliot-Curie was admitted to the Curie Hospital in Paris, where she died on 17 March at the age of 58 from leukemia, possibly due to radiation from polonium-210. Frédéric's health was also declining, and he died in 1958 from liver disease, which too was said to be the result of overexposure to radiation.
Joliot-Curie was an atheist and anti-war. When the French government held a national funeral in her honor, Irène's family asked to have the religious and military portions of the funeral omitted. Frédéric was also given a national funeral by the French government.
Joliot-Curies daughter, Hélène Langevin-Joliot, went on to become a nuclear physicist and professor at the University of Paris. Joliot-Curies son, Pierre Joliot, went on to become a biochemist at Centre National de la Recherche Scientifique.