1,2-Dibromoethane, ( DBE) also known as ethylene dibromide (EDB), is the organobromine compound with the chemical formula (CH2Br)2. It is produced by the reaction of ethylene with bromine, in a classic halogen addition reaction:

    CH2=CH2 + Br2 → BrCH2CH2Br

Historically, 1,2-dibromoethane was used as an anti-knock additive in leaded fuels. It reacts with lead residues to generate volatile lead bromides, thereby preventing fouling of the engine.