He is the son of the current sultan, Sultan Mizan Zainal Abidin, and assumed the regency from 2006 to 2011 during his father"s term as Yang di-Pertuan Agong. Tengku Muhammad Ismail was born 1 March 1998 as the second child and first son of Tengku Mizan Zainal Abidin, the Yang di-Pertuan Muda (Crown Prince) of Terengganu, and Sultanah Nur Zahirah. His father became the Sultan of Terengganu shortly after his birth, after which his mother became known as Permaisuri Nur Zahirah.
He was appointed Yang di-Pertuan Muda (Crown Prince) on 12 January 2006. After Sultan Mizan was elected as Yang di-Pertuan Agong, he appointed Tengku Muhammad Ismail, then aged eight, as Regent on 12 November 2006. Because of Tengku Muhammad Ismail"s young age, a Regency Advisory Council was established to discharge his duties for him.
He was proclaimed as regent during a ceremony on 12 December.
As regent, he presided over the swearing in of Menteri Besar Ahmad Said following the 2008 general election. On 30 August 2010, upon reaching age 12 (baligh, the Islamic age of puberty), Tengku Muhammad Ismail was formally installed as Regent during a ceremony at Istana Maziah.
A Regency Representative Council was formed to discharge his duties as regent while he left the country to pursue his studies. Like his father, Tengku Muhammad Ismail is an equestrian, and has participated in international events.
In June 2010, he finished in second place in the 90 km race at the RTES/Doctorate"Armor French Open in Corlay.
Malaysian First Class of the Family Order of (Denmark I,12 December 2006) Knight Grand Companion of the Order of Sultan Mizan Zainal Abidin of (SSMZ).
The council consisted of Sultan Mizan"s brother Tengku Mustaffa Kamel, and previous members of the Regency Advisory Council, Tengku Sulaiman and Abdul Kadir Sulaiman. Member of the Royal Family Order of Terengganu (DKR, 14 December 2011).
