He was born 12 April 1945 in Seoul, South Korea. Lee obtained a medical degree from Seoul National University, then enrolled at the University of Hawaii to study public health, earning a Master's degree. He joined the WHO in 1983, working on a variety of projects including the Global Programme for Vaccines and Immunizations and Stop Tuberculosis. He began his term as Director-General of WHO on 21 July 2003, having been elected two months before. He was the first Korean to lead an international agency. He died on 22 May 2006 - while in office - in Geneva, Switzerland, following surgery for a blood clot on his brain (a subdural hematoma). He was posthumously awarded the Hibiscus Cordon (Grand Cross) of the Order of Civil Merit by the South Korean government.
In 2004, he was one of the 100 people who shapes our lives and most powerful people in the world by Time Magazine.
He met and later married Kaburaki Reiko, a Japanese woman who visited Korea in order to help out there.
In 1981, Lee and his wife went together to American Samoa to help the poor. In Samoa, he worked in the Lyndon B. Johnson tropical medical center from June 26, 1981 to May 26, 1983. He was known as the Schweitzer of Asia.
He started his work as an advisor on leprosy, and later also treated tuberculosis and promoted the vaccination of children against preventable diseases.
In 1994, Lee moved to Geneva to work at WHO headquarters as chief in prevention and vaccines. In 1995, he was nicknamed Vaccine Czar according to Scientific American.
The 3 by 5 policy which was the basic idea of Dr. Lee was largely criticized by many concerned people. Many, including Joep Lange, the president of the International Aids Society, had a comment that the project was “totally unrealistic”. Médecins sans Frontières, also expressed similar reservations toward Lee's plan.
He worked tirelessly, visiting 60 countries in the three years of his Generalship including Darfur, Sudan, sites of the Indian Ocean tsunami, Madagascar, Mauritius. He was famed as a man of action during this time. His adventurous spirit led him to "experience more, see more, and do more," said his son Tadahiro.
After his death, several people expressed deep grief. Secretary General of United Nations at that time, Kofi Annan mentioned
The world has lost a great man today. He was a strong voice for the right of every man, woman, and child to health prevention and care, and advocated on behalf of the very poorest people.
President George W. Bush of United States said
Dr. Lee worked tirelessly to improve the health of millions of people, from combating tuberculosis and HIV/AIDS to his aggressive efforts to eradicate polio. He provided tremendous leadership to the international community as it confronted the challenges of the 21st century, including the threat of an influenza pandemic. Dr. Lee's outreach to world leaders and entities increased awareness of potentially devastating public health dangers.
Starting in 2009, the awards would be given for mainly the two fields "Young Leadership" and "Contributor of health management" (especially for epidemics) at the annual assembly of World Health Organization which takes place in May each year.