Theodorus (Theo) Bitter (16 December 1916 – 13 February 1994 in The Hague) was a Dutch graphic artist, painter and draftsman.
He also made monumental art, designed textiles, and illustrated books.
Bitter was educated at the Royal Academy of Arts in the Hague.
Bitter co-founded the artistic group Hague Verve with Dirk Bus and was a member of the Pulchri Studio.
Bitter taught Margreet van Dulmen, Hubert Herbergh, Leonie Kording, Ronnie Meerts, Henry Oostenbrink, Piet Smissaert, and L.D.