Feldmarschalleutnant Alfred Johann Theophil Jansa von Tannenau, (July 16, 1884 in Stanislawow – December 20, 1963 in Vienna) was an Austrian Army Officer.
During World War I he held different positions on the Serbian, Italian and Russian fronts, to include being Austrian liaison officer to the Bulgarian Army (1915–1916).
In 1930 he was the Commander of the Niederösterreich Brigade, until 1933, when he was appointed the Austrian Military attaché in Berlin. Afterwards he was made Chief of Staff of the Austrian Army in 1936.
Prior to the Anschluss Jansa and his staff had developed a scenario for Austria's defence against a German attack. Chancellor of Austria Schuschnigg was under considerable pressure from Germany, to include the demand to remove Jansa from his office. The Berchtesgaden agreement (February 12, 1938) stipulated in paragraph 8, that Jansa should be replaced with Franz Böhme. Jansa retired from the army on February 17, 1938.
His father, Emanuel Jansa, was an Oberst in the Austro-Hungarian Army; his mother was Anna von Meyer. He married Judith Reviczky von Revisnye, on April 8, 1919.