DDE is a three-letter abbreviation that may refer to:
In mathematics:
- Delay differential equation
- Directional derivative estimation
In computing:
- Direct data entry
- Double data entry
- Dynamic Data Exchange
Other:
- Department of Distance Education - a school at Fort Leavenworth
- D.D.E., a Norwegian rock band
- Deep-dose equivalent, a measure of radiation absorbed by the body
- Dichlorodiphenyldichloroethylene, which results from the breakdown of DDT
- Digital Diesel Electronics, from BMW
- Direction Départementale de l'Équipement, French road equipment government bureau
- Doctrine of double effect
- DuPont Dai Nippon Engineering, a joint partnership between DuPont and Dai Nippon Printing
- Dwight D. Eisenhower, US president
- Escort destroyer, a US Navy classification for destroyers used between 1945 and 1962
- DDE, a common phrase for describing a DQ