Count Wilhelm Kinsky von Wchinitz (; ; 1574 - 25 February 1634) was a Czech landowner and a statesman. By birth, he was member of the House of Kinsky, which belonged to the highest circle of Bohemian aristocracy.
Wilhelm was born as the younger son of Johann Kinsky von Wchinitz, Burggraf of Karlštejn (1540-1590) and his wife, Anna Pauzar von Michnic (d. 1598), daughter of Johann Pauzar von Michnic.
In 1628, Wilhelm Kinsky was elevated to the rank of Count in the Bohemian nobility when Wallenstein was elevated to Duchy of Friedland. As a rich landowner in Bohemia, Kinsky lived in exile at Dresden after the Battle of White Mountain, because he was a Protestant and, unlike the members of the Trčka family, had refused to convert to the Catholic faith but was allowed to regularly visit his Bohemian estates. Subsequently, together with his brother-in-law Adam Erdmann Trčka, he attempted to pull Wallenstein over to the Protestant and Swedish side.
Kinsky was assassinated during the Thirty Years' War, on 25 February 1634 at Cheb, together with Trčka and other officers loyal to the general and the Field Marshal himself, during the so-called Eger Bloodbath, a plot to purge the Imperial Army from Albrecht von Wallenstein's supporters. Kinsky's estates, among them Teplice, were confiscated by Emperor Ferdinand II.
Wilhelm Kinsky married Countess Elisabeth Magdalena Trčka von Lípa, whose brother Adam Erdmann Trčka von Lípa was married with Countess Maximiliane von Harrach, a sister of Albrecht von Wallenstein's second wife. They had: