The Cappadocian Greeks (Greek: Έλληνες Καππαδόκες; Turkish: Kapadokyalı Rumlar), or simply Cappadocians, are an ethnic Greek community native to the geographical region of Cappadocia in central-eastern Anatolia; roughly the Nevşehir and Kayseri provinces and their surroundings in modern-day Turkey. There had been a continuous Greek presence in Cappadocia since antiquity, and by at least the 5th century AD the Greek language had become the lingua franca of the region.

In the 11th century Seljuq Turks arriving from Central Asia conquered the region, beginning its gradual shift in language and religion. In 1923, following the mass killing of Christian Ottomans across Anatolia, the surviving Cappadocian communities were forced to leave their native homeland and resettle in Greece by the terms of the Greek–Turkish population exchange. Today their descendants can be found throughout Greece and the Greek diaspora worldwide.

The area known as Cappadocia today was known to the Ancient Persians as Katpatuka, a name which the Greeks altered into Καππαδοκία (Cappadocia). The word is essentially of unknown etymology, but some have argued that it means "the land of beautiful horses".

Before Greeks and Greek culture arrived in Asia Minor, the area was controlled by another Indo-European people, the Hittites. Mycenaean Greeks set up trading posts along the west coast around 1300 BC and soon started colonizing the coasts, spreading Hellenic culture and language. In the Hellenistic era, following the conquest of Anatolia by Alexander the Great, Greek settlers began arriving in the mountainous regions of Cappadocia at this time. This Greek population movement of the 3rd and 2nd centuries BC solidified a Greek presence in Cappadocia. As a result, Greek became the lingua franca of the region's natives. It would become the sole spoken language of the region's inhabitants within three centuries and would remain so for the next one thousand years.

After the death of Alexander the Great, Eumenes of Cardia, one of the Diadochi of Alexander the Great, was appointed satrap of Cappadocia, where he set up Greek settlements and distributed cities to his associates. Eumenes left behind administrators, judges and selected garrison commanders in Cappadocia. In the following centuries the Seleucid Greek Kings founded many Greek settlements in the interior of Asia Minor, and this region would become popular for the recruitment of soldiers. Unlike other regions of Asia Minor where Greeks would settle in cities, most of the Greek settlements in Cappadocia and other interior Anatolian regions were villages. The Hellenistic Kings would make new Greek settlements in Cappadocia and other surrounding regions in order to secure their hold on this volatile region; under their rule Greek settlements would increase in the Anatolian interior.

In the centuries following Alexander the Great's death, Ariarathes, the son of a Persian satrap who formerly controlled Cappadocia, gained control of Cappadocia and left it to a line of his successors, who mostly bore the name of the founder of the dynasty. These kings began to intermarry with neighboring Greek Hellenistic kingdoms, such as the Seleucids. During their reign Greek towns were beginning to appear in the southern regions of Cappadocia. Ariarathes V of Cappadocia who reigned from 163 to 130 BC is considered to have been the greatest of the Kings of Cappadocia. He was predominantly Greek by descent; his father Ariarathes IV of Cappadocia was half Greek Macedonian and Persian, and his mother was Antiochis, the daughter of the Seleucid Greek King Antiochus III of the Seleucid dynasty. By the 1st century BC, regions of Cappadocia had been ravaged by Armenian King Tigranes the Great, who had relocated a great number of Cilician and Cappadocian Greeks to Mesopotamia (geographically in modern Iraq, eastern Syria and south-eastern Turkey.)

Archelaus, who was a Roman client prince, was the last to rule as a king of Cappadocia. He was a Cappadocian Greek nobleman, possibly of Macedonian descent, and was the first king of Cappadocia of wholly non-Persian blood. He ruled over Cappadocia for many years before being deposed by Tiberius, who took possession of Cappadocia for Rome. The region of Cappadocia produced some notable Greek individuals in antiquity, such as Apollonius of Tyana (1st century AD) who was a Greek Neo-Pythagorean philosopher who became well known in the Roman Empire and Aretaeus of Cappadocia (81–138 AD) who was a native Greek, born in Cappadocia and is considered to have been one of the foremost surgeons in antiquity. He was the first to distinguish between diabetes mellitus and diabetes insipidus, and the first to provide a detailed description of an asthma attack.

By late antiquity the Cappadocian Greeks had largely converted to Christianity. They were so thoroughly devout to Christianity that by the 1st century AD, the region of Cappadocia served as a stronghold for Christian Monasticism and was of significance importance in the history of early Christianity. In the early centuries of the Common Era Cappadocia produced three prominent Greek patristic figures, known as the three hierarchs. They were Basil the Great (c. 330–79), Bishop of Caesarea in Cappadocia. Gregory of Nazianzus (c. 330–c. 389) (later known as Saint Gregory the Theologian) and Gregory of Nyssa (died c. 394). These Cappadocian Greek fathers of the fourth century revered the ancient Greek cultural pursuit of virtue, even studying Homer and Hesiod and "stood squarely in the tradition of Greek culture".