AED may refer to:
- Anhidrotic ectodermal dysplasia, a genetic disorder
- Automated external defibrillator, a portable electronic device that diagnoses and can correct arrhythmia of the heart.
- AED (non-profit), formerly known as the Academy for Educational Development
- Accident and emergency department
- Advertising elasticity of demand, a measure of the effectiveness of advertising
- AED Oil Limited, an oil exploration and production company
- ALGOL Extended for Design, an extended version of the ALGOL programming language
- Alpha Epsilon Delta (ΑEΔ), an American premedical honor society
- 5-Androstenediol, an adrenal gland hormone that stimulates marrow-cell growth
- Antiepileptic drugs, a type of medication used to treat epileptic seizures
- Atomic-emission detector, a type of chromatography detector
- Auger electron diffraction
- AED, ISO 4217 currency code of the United Arab Emirates dirham, the currency of the United Arab Emirates