Head of the Arab and Islamic Relations Portfolio and Hamas deputy chief in the Gaza Strip, Dr. Khalil al-Hayya, was born on 5 November 1960 in Gaza City.
Al-Hayya received his elementary and secondary education in Gaza City.
In 1982, Al-Hayya was elected as president of the IUG's Student Council.
In 1983, Al-Hayya graduated with a bachelor's degree from the Faculty of Religious Fundamentals at the Islamic University of Gaza's (IUG).
Six years later, Al-Hayya did a master's degree in Prophetic Hadith at the University of Jordan.
Al-Hayya continued his higher education and finished a PhD in Hadith at the University of the Holy Quran and Islamic Sciences in Sudan in 1997.
Al-Hayya worked as a lecturer at the IUG's Faculty of Religious Fundamentals (Osool Eddin).
He was elected as deputy chief of the IUG's staff association in 1985 before being appointed as its chief 14 years later.
Al-Hayya, who was also a member of the Palestine Scholars Association, was nominated as Dean of Students Affairs at the IUG in 2001.
In 2006, Al-Hayya was elected as a member of the Palestinian Legislative Council (PLC) and served as head of Hamas' Change and Reform bloc in the parliament.
In the early 1990s, Al-Hayya was imprisoned by the Israeli occupation authorities for more than three years.
In 2007, Al-Hayya survived an assassination attempt after Israeli occupation warplanes bombed his house, killing seven members of his family.
His son, Hamza, was killed in an Israeli drone strike in the Shejaiya neighborhood in eastern Gaza City one year later.
As a representative for Hamas, Al-Hayya played a pivotal role in the ceasefire fire talks with the Israeli occupation during its 2014 military offensive on the Gaza Strip.
During its 2014 onslaught on Gaza, the Israeli occupation army fired artillery shells at his home in the Shejaiya neighborhood, seriously injuring his wife and killing his son, Osama, his wife, and three of their children.
In 2017, Al-Hayya was elected as Hamas's deputy chief in the Gaza Strip.