Queen Elizabeth II
UK: 59 years
King Bhumibol Adulyadej
Thailand: 64 years
Sultan Abdul Halim of Kedah
Malaysia: 1952
Hassanal Bolkiah
Brunei: 1943
Qaboos Bin Said
Oman: 40 years
Muammar Gaddafi
Libiya – 40 years
Queen Margrethe II
Denmark: 39 years
King Carl XVI Gustaf
Sweden: 37 years
King Juan Carlos I
Spain: 35 years
President Ali Abdullah Saleh
Yemen: 31 years
José Eduardo
Angola: 1931
Robert Mugabe
Zimbabwe: 30 years
Prince Khalifa bin Salman Al Khalifa
Bahrain: 30 years