Gusztáv Hennyey (25 September 1888 – 14 June 1977) was a Hungarian politician and military officer, who served as Minister of Foreign Affairs in 1944 for a month.

After the First World War he worked as a military attaché in Paris, Belgrade and Athens.

After the Arrow Cross Party's coup (15 October 1944) he was arrested along with most of the ministers and moderate, magisterial politicians.

Hennyey was taken to Sopron and later Bavaria, when the Soviet Red Army approached continually.

The Office of Strategic Services captured Hennyey but set him free, stating, that he was not considered a war criminal.