Egeland assumed his post as the Under-Secretary-General (USG) for Humanitarian Affairs and Emergency Relief Coordinator (ERC) in August 2003. This position is the head of the UN Office for the Coordination of Humanitarian Affairs (OCHA). He was preceded in the post by Kenzo Oshima of Japan.

Prior to becoming the head of OCHA, Egeland was the Secretary General of the Norwegian Red Cross. From 1999 to 2002, he was the United Nations Secretary-General's Special Adviser on Colombia. Egeland's career also includes service to his government as State Secretary in the Norwegian Ministry of Foreign Affairs from 1990 to 1997. In that capacity, he initiated two Norwegian Emergency Preparedness Systems, which have provided more than 2,000 experts and humanitarian workers to international organizations. He has also been Chair of Amnesty International in Norway, and Vice-Chair of the International Executive Committee of Amnesty International, which he was elected on to at the age of 23, the youngest ever to hold the position. He served as Director for the International Department of the Norwegian Red Cross, Head of Development Studies at the Henry Dunant Institute in Geneva and a radio and television international news reporter for the Norwegian Broadcasting Corporation.

Egeland holds a Magister Artium in Political Science from the University of Oslo. He has been a Fulbright Scholar at the University of California, Berkeley and a fellow at the International Peace Research Institute, Oslo, and the Truman Institute for the Advancement of Peace, Jerusalem.

As mentioned in his official biography, Jan Egeland studied at Truman Institute for the Advancement for Peace in Jerusalem. His impartiality in the Lebanon conflict as an honest broker is being questioned by Hezbollah and various other groups in Lebanon. He has been accused by the Lebanese government and media of not focusing sufficiently on the humanitarian crises on Lebanon, while being critical about rocket attacks on Israel. In a United Kingdom Channel 4 interview Egeland laid the blame on the crisis in Lebanon on Hezbollah who he said "Hide amongst the civilian population and which gives the Israeli air force no choice but to attack civilian structures," though he also has referred to the Israeli strikes as "a violation of humanitarian law,".

He is married, and has two daughters. In 2006, Time magazine named him one of the 100 "people who shape our world".

In 2008 Egeland published a memoir A Billion Lives: An Eyewitness Report from the Frontlines of Humanity about his time at the UN from 2003-2006.

He has published a number of reports, studies and articles on conflict resolution, humanitarian affairs and human rights.