However, for the greater part of the last millennium, Phuket was known as Junk Ceylon, which, with variations, is the name found on most old maps. The name is thought to have its roots in Ptolemy's Geographia, written by the Alexandrian geographer in the 3rd century AD. He mentioned that in making a trip from Souwannapum to the Malay Peninsula, it was neccesary to pass the cape of Jang Si Lang.

Phuket was a way station on the route between India and China for seafarers to stop for shelter. The island appears to have been part of the Shivite empire (called the Tam Porn Ling in Thai) that established itself on the Malay Peninsula during the first millennium AD. Later, as Muang Takua-Talang, it was part of the Srivichai and Siri Tahm empires. Governed as the eleventh in a constellation of twelve cities, Phuket's emblem, by which it was known to others, in those largely pre-literate times, was the dog.

During the Sukothai Period, Phuket was associated with Takua Pa, in what is now Phangnga Province, and another area with vast tin reserves. The Dutch established a trading post during the Ayuthaya Period of the 16th century. The island's northern and central regions were governed by the Thais, and the southern and western parts were given over to the tin trade, a concession in the hands of foreigners.

After Ayuthaya was sacked by the Burmese in 1767, there was a short interregnum in Thailand, ended by King Taksin, who drove out the Burmese and re-unified the country. The Burmese, however, were anxious to return to the offensive. They outfitted a fleet to raid the southern provinces, and carry off the population to slavery in Burma.

This led to Phuket's most significant historic event. A passing sea captain, Francis Light, sent word that the Burmese were en route to attack. Forces in Phuket were assembled by two heroines, Kunying Jan, wife of the recently deceased Phuket governer, and her sister, Mook, After a month's siege, the Burmese were forced to depart on 13 March, 1785. Kunying Jan and her sister were credited with the successful defense.

In recognition, King Rama I bestowed upon Kunying Jan the honorific Thao Thepkrasatri, a title of nobility usually reserved for royalty. Her sister became Thao Srisunthorn.

During the 19th century, Chinese immigrants arrived in such numbers to work for the tin mines that the ethnic character of the island's interior became predominantly Chinese, while the coastal settlements remained populated chiefly by Muslim fishermen.

In Rama V's reign, Phuket became the administrative center of a group of tin mining provinces called Monton Phuket, and in 1933, with the change from absolute monarchy to a parliamentary system, the island was established as a province by itself.