OEA may refer to:

• Oea, the Phoenician name for Tripoli, Libya
• Office of Economic Adjustment
• Ohio Education Association
• Oleoylethanolamide, an endogenous peroxisome proliferator-activated receptor alpha (PPAR -a) agonist
• Oregon Education Association
• Organización de los Estados Americanos (Organization of American States), a group dedicated to strengthening ties in the western hemisphere
• O'Neal Airport's IATA code
• Operadora Estatal de Aeropuertos, a Mexican airline agency and owner of Hermanos Serdán International Airport
• Office of the Employment Advocate, Australian agency now subsumed under the Workplace Authority

Oea was a Roman colony in Berber Africa. It was originally founded by the Phoenicians. As part of the Roman Africa Nova province, Oea and surrounding Tripolitania was prosperous and reached a golden age in the 2nd and 3rd centuries, when the city (mainly thanks to the Severan dynasty originated from nearby Leptis Magna) was at its height. Oea is now called Tripoli in modern Libya.