Teylingen Castle (Dutch: Slot Teylingen) is a Dutch castle in the municipality of Teylingen, in the town of Voorhout, near the border with Sassenheim. It is presumably the family keep of the noble family Van Teylingen.

The castle was originally built to protect the north-south route in Hollandic territory. Later it became a forester’s castle for the forestry of the counts of Holland, starting with William IV, count of Holland.

At present, only the ruins of the castle remain. These remnants are well preserved, and consist of a surrounding wall and a donjon which forms part of the wall partially surrounded by water. The wall dates from the beginning of the 13th century and the main building shortly thereafter. The castle was damaged heavily around 1570 during the Eighty Years’ War, and partially restored thereafter. The donjon was partially burnt in 1675 and after which decay set in, and further parts were gradually demolished. 

The municipality of Teylingen is named after the castle, partly because the name Teylingen was also present in the three former municipalities Sassenheim, Voorhout and Warmond.