Tan Sri Datuk Zainun Ali was born on April 5, 1952 in Johor Bahru. She received her early education at Yahya Awal Primary Girls’ School and thereafter at Sultan Ibrahim Secondary Girls’ School in Johor Bahru. Tan Sri Zainun then obtained a Bachelor’s Degree of Laws (LL.B.) (Hons) from Universiti Malaya, Kuala Lumpur and, thereafter obtained Master’s Degree of Law (LL.M.) (Cantab) from the University of Cambridge, United Kingdom. Upon graduation, Tan Sri Zainun held various positions in the legal and judicial services since 1976.
Tan Sri Datuk Zainun Ali started her career in March 1976 as Legal Officer and appointed as Magistrate in 1979. Fast forward to August 1996, Tan Sri Datuk Zainun Ali was appointed as Judicial Commissioner, High Court of Malaya, Kuala Lumpur. In 1998 – 2001, Tan Sri Datuk Zainun Ali was elevated to be High Court Judge, Shah Alam, Johor and Kuala Lumpur and then in 2006, she was appointed as Court of Appeal Judge, Malaysia, then in 2012 – 2018, she was elevated to be Federal Court Judge, Malaysia
Tan Sri Datuk Zainun Ali had held a number of membership posts, such as: a Member of the Board of Advisory, Faculty of Law, Universiti Malaya; a Member of Board of Studies, Ahmad Ibrahim Kuliyyah of Law, International Islamic University; and a Member of Judicial & Legal Services Association. Tan Sri Datuk Zainun Ali retired from the Malaysian Judiciary in October 2018.
Tan Sri Datuk Zainun Ali is currently appointed as the Chairman of Malaysia Airports Berhad; Chairman of İstanbul Sabiha Gokcen Airport, Turkey; Pro-Chancellor of Universiti Malaya; Director of Permodalan Nasional Berhad; Deputy Chaiman of Enforcement Agency Integrity Commission; Board Member of the United Nations Global Judicial Integrity Network Advisory Board; Member of Advisory Tribunal of the Islamic Development Bank of Jeddah; registered Arbitrator of Asian International Arbitration Center; Director of Allianz Malaysia Berhad; and Consultant of Zain & Co. Law Firm.
Tan Sri Datuk Zainun Ali was appointed as one of the ten members of the United Nations Office on Drug and Crime Advisory Board of the Global Judiciary Integrity Network on April 10, 2018 which was established to promote judicial integrity amongst judges and stakeholders.
In recognition of her public services, Tan Sri Datuk Zainun Ali was bestowed a few awards by the State including Kesatria Mangku Negara (K.M.N.) in 1991, Setia Mahkota Johor (S.M.J.) in 2001, Panglima Jasa Negara (P.J.N.) in 2002 - which carries the title “Datuk”, and Panglima Setia Mahkota (P.S.M) in 2015 – which carries the title “Tan Sri”.