ओक्लाहोमा हे अमेरिकेचे एक राज्य आहे. अमेरिकेच्या दक्षिण भागात वसलेले ओक्लाहोमा क्षेत्रफळाच्या दृष्टीने अमेरिकेमधील २०वे तर लोकसंख्येच्या दृष्टीने २८व्या क्रमांकाचे राज्य आहे. अमेरिकेच्या संघात सामील झालेले ओक्लाहोमा हे ४६वे राज्य आहे.

Oklahoma is a landlocked state in the South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northeast, Arkansas to the east, New Mexico to the west, and Colorado to the northwest. Partially in the western extreme of the Upland South, it is the 20th-most extensive and the 28th-most populous of the 50 United States. Its residents are known as Oklahomans and its capital and largest city is Oklahoma City. The state's name is derived from the Choctaw words okla, 'people' and humma, which translates as 'red'. Oklahoma is also known informally by its nickname, "The Sooner State", in reference to the Sooners, American settlers who staked their claims in formerly American Indian-owned lands until the Indian Appropriations Act of 1889 authorized the Land Rush of 1889 opening the land to settlement.