Cornelis Melyn (1600 – c. 1662) was an early Dutch settler in New Netherland and Patroon of Staten Island. He was the chairman of the council of eight men, which was a part of early steps toward representative democracy in the Dutch colony.

Cornelis Melyn was born in Antwerp, then a part of the Spanish Netherlands, where he was baptised at St. Walburga Church September 17, 1600, the son of Andries and Maria (Gheudinx-Botens) Melyn, and grandson of Lambrecht Melyn, of the same place. Both of Cornelis' parents died in 1606. Two guardians, Jacques Melyn and Hans Salomons, were appointed for him and he was taken into the family of his half-brother Abraham Melyn to be raised. When he was about twelve years of age, Cornelis was apprenticed as a tailor.

When Melyn was about 18 years old, the priest of St. Walburga Church issued him a baptismal certificate and a certificate of good conduct. It is possible he left Antwerp at this time for Amsterdam, where he married Janneken Adriaens in 1627. Their marriage certificate lists them both as residing in Amsterdam. By this time, Melyn had changed his occupation, being listed in this certificate as a seemtouwer, a "dresser of the finer and softer leathers".

Cornelis Melyn made at least one voyage to the New World before deciding to settle there, as supercargo aboard the Dutch West India Company's ship Het Wapen van Noorwegen (The Arms of Norway) in 1638. After returning to the Netherlands, he applied for the Patroonship of Staten Island, which he was granted July 3, 1640. Soon afterwards, he sailed, possibly in the Engel Gabriel (Angel Gabriel), for New Netherland. But the vessel was captured by a Dunkirk raider August 13, 1640, and Melyn was forced to return to the Netherlands.

Melyn sailed once again to New Amsterdam May 17, 1641, aboard the vessel Den Eyckenboom (The Oak Tree) with a new party of colonists, including his wife and children. Also on board was Adriaen van der Donck who would one day be a political ally of Melyn and a fellow victim of Director-General Peter Stuyvesant's persecution. Soon after arrival of Den Eyckenboom in New Amsterdam, Cornelis Melyn and his party of 41 persons were at work establishing a new colony on Staten Island. June 19, 1642, Melyn received from Director-General Willem Kieft his patent to all of Staten Island except for a farm which had already been allocated to David Pietersen de Vries.

In November 1643, during the bloody conflict with the neighboring Lenape tribes which became known as Kieft's War, Melyn and his colonists were forced to abandon Staten Island. According to his own statement, "I was obliged to flee for the sake of saving my life, and to sojourn with wife and children at the Menatans till the year 1647."

In 1644, his plantation having been destroyed, Cornelis Melyn purchased three adjacent lots near the Dutch fort on lower Manhattan, along the East River near the intersection of the present Broad and Pearl Streets. He settled there with his family for the next three years. As the Dutch colony drifted into chaos and some colonists expressed outrage at what they considered Kieft's ineptitude, the Director-General sought to placate his critics by appointing a council of eight men, with Cornelis Melyn as chairman, to assist him in governing the colony. This body, which was supposed to represent the people of New Amsterdam, was one of the earliest steps toward representative democracy in that colony. The colonists' opposition to Kieft continued, however, and the council demanded his removal in a letter transmitted to the States-General of the Netherlands in October 1644.

Melyn is attributed with having written the Breeden Raedt, considered one of the earliest descriptions of life in the colony and condemnation of Dutch West Indies Company policies.