The Declaration of Neutrality was a declaration by the Austrian Parliament declaring the country permanently neutral. It was enacted on 26 October 1955 as a constitutional act of parliament, i.e., as part of the Constitution of Austria.

Formally, the declaration was promulgated voluntarily by the Republic of Austria. Politically, it was the direct consequence of the allied occupation by the Soviet Union, the United States, the United Kingdom, and France between 1945 and 1955, from which the country was freed by the Austrian State Treaty of 15 May the same year. The Soviet Union would not have agreed to the State Treaty if Austria had not committed herself to declare her neutrality after the allied forces had left the country.