AAU

AAU most commonly refers to:
 * Association of American Universities, a selective group of 71 major research universities in North America

AAU may also refer to:

Education

 * Aalborg University, in Denmark
 * Academy of Art University, in San Francisco, California, United States
 * Addis Ababa University, in Ethiopia
 * Allied American University, Laguna Hills, California, United States
 * Alpen-Adria-University of Klagenfurt, in Austria
 * Anand Agricultural University, in Anand, Gujarat, India
 * Anglo-American University, in Prague, Czech Republic
 * Antillean Adventist University, in Mayagüez, Puerto Rico
 * Assam Agricultural University, in Jorhat, Assam, India
 * Association of African Universities

Healthcare

 * Acute assessment unit, in a UK hospital
 * Acute anterior uveitis, an inflammation of the middle layer of the eye

Other uses

 * AAU, a codon for the amino acid asparagine
 * Abau language, a language of Papua New Guinea
 * Allgemeine Arbeiter-Union – Einheitsorganisation, a German communist organisation
 * Alpha acid unit, a measure of the bitterness of hops used in brewing beer
 * Amateur Athletic Union, an amateur sports organization in the United States
 * Amendment to allege use, a legal term
 * Asau Airport in Asau, Samoa
 * Assigned amount units, emission allowances created and allocated under the Marrakech Accords of the Kyoto protocol
 * Americanos U.S.A., an American bus company