Martens suffered from pancreatic cancer and ended his life via euthanasia on the 9th of October, 2013 at his home in Lokeren; he was 77. Elio Di Rupo, the Belgian prime minister, described him as a "true statesman and one of the fathers of federal Belgium". Martin Schulz, president of the European Parliament, paid tribute to him as a "statesman of Belgium, Europe and an outstanding leader of European Parliament". Jerzy Buzek, EPP MEP and former prime minister of Poland, described him as "irreplaceable".