Djédjé graduated from the National School of Administration of Abidjan and from the Institute of Political Studies at the University of Lyon II. He held posts at the Ivorian Ministry of Foreign Affairs from 1987 to 1994. He was First Secretary and Consul at the Ivorian Embassy in South Africa from 1994 to 2000, then returned to the Ministry of Foreign Affairs as Assistant Director of diplomatic privileges and immunities, holding that post from 2002 to 2005.
In January 2005, Djédjé was appointed as Special Adviser of President Laurent Gbagbo. After two years in that post, he became Permanent Representative to the UN, presenting his credentials on January 11 2007.