Crimean Tatars (Crimean Tatar: qırımtatarlar, къырымтатарлар), or simply Crimeans (qırımlılar, къырымлылар), are an Eastern European Turkic ethnic group and nation indigenous to Crimea. Their ethnogenesis lasted thousands of years in Crimea and the northern regions along the coast of the Black Sea, uniting Mediterranean populations with those of the Eurasian Steppe.

Until the 20th century, Crimean Tatars were the most populous demographic cohort in Crimea, constituting the majority of the peninsula's population as a whole. Following the Russian Empire's annexation of the Crimean Khanate in 1783, they were subjected to attempts at driving them from the region through a combination of physical violence and harassment, forced resettlement, and legalized forms of discrimination. By 1800, between 100,000 and 300,000 Crimean Tatars had left Crimea.

While Crimean Tatar cultural elements were not completely eradicated under the Romanov dynasty, the populace was almost completely eradicated from the peninsula under the Soviet Union, especially during the Stalinist era. In May 1944, almost immediately after the Soviets retook German-occupied Crimea during World War II, the country's State Defense Committee ordered the deportation of all Crimean Tatars, including the families of Crimean Tatar soldiers in the Red Army. The deportees were transported in trains and boxcars to Central Asia, where they were primarily resettled in Uzbekistan. Anywhere from 18% to 46% of the Crimean Tatar population was lost due to the Soviet deportation campaigns. From 1967 onwards, only a few of the displaced Crimean Tatars were allowed to return, although de-Stalinization had led to the Soviet government's recognition of the deportations as ethnic cleansing and cultural genocide. Later, in 1989, the Supreme Soviet of the Soviet Union adopted new policies for the full right of return of the Crimean Tatars, sparking a steady increase in the population.

Since the dissolution of the Soviet Union in 1991, the Crimean Tatars have been members of the Unrepresented Nations and Peoples Organization. The European Union and international indigenous groups do not dispute their status as an indigenous people and they have been officially recognized as an indigenous people of Ukraine since 2014. However, the Russian administration in occupied Crimea considers them a "national minority" instead of an indigenous people, and continues to deny that they are the peninsula's titular nation, in spite of the fact that the Soviet administration considered them indigenous before their deportation. Today, Crimean Tatars constitute approximately 15% of the Crimean population. Beyond the peninsula, significant populations of the Crimean Tatar diaspora exist in Turkey, Romania, and Bulgaria, among other countries.

The Crimean Tatar language is a member of Kipchak languages of the Turkic language family. It has three dialects and the standard language is written in the central dialect. Crimean Tatar has a unique position among the Turkic languages because its three "dialects" belong to three different (sub)groups of Turkic. This makes the classification of Crimean Tatar as a whole difficult.

UNESCO ranked Crimean Tatar as one of the most endangered languages that are under serious threat of extinction (severely endangered) in 2010. However, according to the Institute of Oriental Studies, due to negative situations, the real degree of threat has elevated to critically endangered languages in recent years, which are highly likely to face extinction in the coming generations.

The Crimean Tatars are most often subdivided into three core sub-ethnic groups:

There are also three other groups that are closely related to Crimean Tatars and sometimes are considered as sub-ethnic groups: