Jacob Collaart or Collaert (floruit c. 1625–1637) was a Flemish admiral who served as privateer and one of the Dunkirkers in Spanish Habsburg service during the Dutch Revolt.

From 1633 until 1637, Collaart served as Vice Admiral with the Royal Squadron operating out of Dunkirk and, in 1635, his attacks against Dutch herring redders would cost the city of Flushing (Vlissingen) over two million guilders in income.

On 19 August, after chasing off the six men-of-war escorts, Collaart's forces destroyed around 50 herring boats near Dogger Bank.

Of the surviving fishermen, 150 sailors including wounded as well as the young and the elderly were put on a merchant vessel from Hamburg and returned to the Dutch Republic while the remaining 775 were held captive for ransom.

In part due to bad weather, Collaart was able to escape to Dunkirk, arriving with 975 captive fisherman on 8 September 1635.