Leo Prochownik was a German figure, landscape and marine painter, etcher and illustrator.

Leo Prochownik's parents were David and Ottilie Prochownik, née Robinson (1845-1911). Before he started school, the family moved to Bremen, then to Berlin. David Prochownik ran an import company for perfumery goods with his brothers Wilhelm and Jonas in Berlin, Ritterstraße 45.

After leaving school, Leo Prochownik joined a decoration company as an apprentice. In this context, he was involved in the interior painting of the Kroll Opera House, among other things. At the same time, he studied at the Berlin Museum of Decorative Arts. In October 1895, he went to Munich for further training, but returned to Berlin in 1896, where he worked as an illustrator and advertising artist. In June 1897, he began his studies at the Dresden Academy of Art, where he studied under Bantzer and Gotthard Kuehl. In 1904 he returned to Berlin, and in January 1905 he was accepted as a master student of Karl Köpping at the Berlin Academy of Arts.

In 1909, Prochownik married Gertrud Borgzinner (1884-1982). After a short stay in Copenhagen, they returned to Berlin, where they initially lived in Berlin-Steglitz, and from 1912 onwards in Landauer Straße near Rüdesheimer Platz.

In January 1917, Prochownik was called up for military service. He fell ill soon afterwards and was discharged from military service in March 1917 after a stay in the Kortau military hospital.

Their daughter Marianne was born in 1919.

From 1925, Leo Prochownik came into contact with Jewish intellectuals through the professional activities of his wife Gertrud, who had taken over the Arbeitsgemeinschaft jüdischer Arbeitsnachweise in Berlin. Among others, the family was friends with Salomon Adler-Rudel. He produced a series of portraits of Jewish youths whom he had met at the Jewish People's Home. The original intention was to publish the portraits in a book.

Leo Prochownik worked as an illustrator for the magazine Jugend, among others. He made landscape sketches on vacation trips to Liseleje and Rügenwaldermünde, as well as in Cadempino in 1929 and annually in Kloster on Hiddensee from 1930 to 1935.

In 1929, Prochownik joined the Porza artists' association.

He died in 1936 after a long illness. His wife Gertrud survived the Nazi era in hiding with Johanna and Lothar Kreyssig and emigrated to London via Australia. Some of Prochwnik's works were found in the cellar of the Jewish Hospital in Berlin after the Second World War.