Abdullah bin Jassim bin Mohammed Al Thani, also known as Sheikh Abdullah bin Jassim Al Thani or Sheikh Abdullah bin Qassim Al Thani, was the Emir of Qatar. He was born in 1880 in Doha, the capital city of Qatar. He then abdicated in favour of his crown prince and second son, Sheikh Hamad bin Abdullah Al Thani, in 1940. Sheikh Hamad died eight years later and Sheikh Abdullah assumed office once again until 1949, when he stepped down from office in favour for his eldest son, Sheikh Ali bin Abdullah Al Thani. Oil was also discovered for the first time during his rule.

The emir of the State of Qatar is the monarch and head of state of the country. The emir is also the commander-in-chief of the Armed Forces and guarantor of the Constitution. The emir holds the most powerful position in the country, and has a prominent role in foreign relations.