Ernst Gronau (21 August 1887 – 10 August 1938) was a German actor and writer.

• Prostitution (1919)
• Genuine (1920)
• Roswolsky's Mistress (1921)
• The Graveyard of the Living (1921)
• Miss Julie (1922)
• The Stream (1922)
• The Curse of Silence (1922)
• The Game with Women (1922)
• Man by the Wayside (1923)
• And Yet Luck Came (1923)
• Liebesbriefe der Baronin von S... (1924)
• Wood Love (1925)
• His Late Excellency (1927)
• Prinz Louis Ferdinand (1927)
• Father and Son (1930)
• I for You, You for Me (1934)

• Jung, Uli & Schatzberg, Walter. Beyond Caligari: The Films of Robert Wiene. Berghahn Books, 1999.

• Ernst Gronau at IMDb