The former prime minister died on Sunday, Turkey's Anatolian state news agency reported.
Mr Ecevit, a left-leaning nationalist and poetry lover whose political career spanned half a century, suffered a stroke on May 18 after attending the funeral of a top judge killed by an alleged Islamist gunman.
He had been in a coma ever since.
During his fifth term as prime minister, Mr Ecevit was partly blamed for an economic meltdown that helped sweep the current government, which has Islamist roots, to power in November 2002.