ELINT stands for ELectronic INTelligence, and refers to intelligence-gathering by use of electronic sensors.

The data gathered is typically pertinent to a rival's defense network, especially the electronic parts such as radars, SAM systems, aircraft, etc. It can be performed from ground stations near the opponent's territory, ships off their coast and aircraft near or in their airspace. The USA is believed to be the premier ELINT expert. They are known to gather data on countries such as Russia (ex-USSR) and China. This has lead to several embarrassing incidents with aircraft or ships straying into hostile waters or airspace and one particularly bad incident where a Chinese MiG fighter collided with a U.S. "spy plane " (accidentally or on purpose) and forced it down into China.

The primary goal of ELINT is to acquire data which would be invaluable in the event of a conflict. Knowing where each SAM and AAA system is and its type means that air raids can be plotted to avoid the most heavily defended areas and to fly on a flight profile which will give the aircraft the best chance of evading ground fire and fighter patrols. It also allows for the jamming or spoofing of the enemy's defence network (see electronic warfare).

ELINT can also acquire data about where the ships, command and control centers, surface-to-air missile systems and other assets of the enemy are so they can be struck in the event of a war. Good electronic intelligence can be very important to stealth operations; stealth aircraft are not totally undetectable and need to know which areas to avoid. For more information, see Stealth. Similarly, conventional aircraft need to know where fixed or semi-mobile air defence systems are so that they can shut them down or fly around them.

Combining other sources of information and ELINT allows traffic analysis to be performed on electronic emissions which contain human encoded messages. The method of analysis differs from SIGINT in that any human encoded message which is in the electronic transmission is not analysed during ELINT. What is of interest is the type of electronic transmission and its location. For example during The Battle of the Atlantic in World War II, Ultra SIGINT was not always available because Bletchley Park was not always able to read the U-Boat Enigma traffic. But "High Frequency Direction Finders" Huff-Duff was still able to find where the U-Boats were by analysis of radio transmissions and the positions through triangulation from the direction located by two or more Huff-Duff systems. The Admiralty was able to use this information to plot courses which took convoys away from high concentrations of U-Boats.