APL is an abbreviation, acronym, or initialism that may refer to:

• Acute promyelocytic leukemia, a subtype of acute myelogenous leukemia
• American President Lines, a Singapore-based container transportation and shipping company
• American Protective League, a WWI era pro-war organization
• Association of Pension Lawyers
• APL programming language, an array programming language invented in 1962
• The Apple Public License
• The Applied Physics Laboratory at Johns Hopkins University
• The Applied Physics Laboratory at the University of Washington
• The United States Navy hull classification symbol for Barracks Craft
• Australian Pork Limited