The Kingdom of Saudi Arabia (Arabic: المملكة العربية السعودية) is the largest country on the Arabian Peninsula. It is bordered by Jordan on the northwest, Iraq on the north and northeast, Kuwait, Qatar, Bahrain, and the United Arab Emirates on the east, Oman on the southeast, and Yemen on the south, with the Persian Gulf to its northeast and the Red Sea to its west.

The Kingdom is sometimes called "The Lands of The Two Holy Mosques" in reference to Mecca and Medina, the two holiest places in Islam. In English, it is most commonly referred to as Saudi Arabia, often as just Saudi or the Kingdom by many English-speaking expatriates in the kingdom, or, less commonly (as in international football events or in the national press) as KSA or SA. Sometimes Arabia is used to refer to the nation, but the term can also refer to the entire Arabian Peninsula. The Arabic short form is usually السعودية but local citizens often just refer to the nation as al-Mamlaka (the Kingdom).

Saudi Arabia is the world's leading petroleum exporter and petroleum exports fuel the Saudi economy. Oil accounts for more than 90 percent of exports and nearly 75 percent of government revenues, facilitating the creation of a welfare state, which the government has found difficult to fund during periods of low oil prices.