Prince Friedrich Karl of Prussia (Tassilo Wilhelm Humbert Leopold Friedrich Karl - Born April 6, 1893 in Schloss Klein-Glienicke, Potsdam, German Empire - Died April 6, 1917 in Saint-Étienne-du-Rouvray, France.

He was the son of Prince Friedrich Leopold of Prussia (1865–1931) and Princess Louise Sophie of Schleswig-Holstein-Sonderburg-Augustenburg (1866–1952) and a grandson of Prince Frederick Charles of Prussia.