An abstract painter, Hosny held exhibitions worldwide and won the Japanese Soka Gakai International University cultural and peace prize.

[7][8] On July 30, 2007, Egypt nominated Hosny to succeed Koichiro Matsuura as Director-General of the United Nations Educational, Scientific and Cultural Organization (UNESCO) and began a campaign to have him elected to the position.

[9] Hosni was regarded as certain to win the September 2009 election, but his May 2008 pledge to burn Israel books in Egyptian libraries sparked doubts about his suitability for the position and strengthened opposition to his candidacy.

[10] In a May 2009 open letter to the international community, the three figures decried that Hosny's victory "would be an obvious provocation so transparently contrary to the proclaimed ideals of the UN that UNESCO would not recover."

"[10] Despite the opposition, Hosny was still expected to win by a large margin, receiving pledges of support from the Arab League, the Organization of African Unity and the Organisation of the Islamic Conference.

Months prior to the UNESCO election, the Israeli government ceased opposition to Hosni's candidacy following a May 2009 meeting between Prime Minister Benjamin Netanyahu and Mubarak.