Ethylamine, also known as ethanamine, is an organic compound with the formula CH₃CH₂NH₂. This colourless gas has a strong ammonia-like odor. It condenses just below room temperature to a liquid miscible with virtually all solvents. It is a nucleophilic base, as is typical for amines. Ethylamine is widely used in chemical industry and organic synthesis. It is a DEA list I chemical by 21 CFR § 1310.02.

Ethylamine is produced on a large scale by two processes. Most commonly ethanol and ammonia are combined in the presence of an oxide catalyst:

In this reaction, ethylamine is coproduced together with diethylamine and triethylamine. In aggregate, approximately 80M kilograms/year of these three amines are produced industrially. It is also produced by reductive amination of acetaldehyde.

Ethylamine can be prepared by several other routes, but these are not economical. Ethylene and ammonia combine to give ethylamine in the presence of a sodium amide or related basic catalysts.

Hydrogenation of acetonitrile, acetamide, and nitroethane affords ethylamine. These reactions can be effected stoichiometrically using lithium aluminium hydride. In another route, ethylamine can be synthesized via nucleophilic substitution of a haloethane (such as chloroethane or bromoethane) with ammonia, utilizing a strong base such as potassium hydroxide. This method affords significant amounts of byproducts, including diethylamine and triethylamine.

Ethylamine is also produced naturally in the cosmos; it is a component of interstellar gases.

Like other simple aliphatic amines, ethylamine is a weak base: the pK_a of [CH₃CH₂NH₃]⁺ has been determined to be 10.8

Ethylamine undergoes the reactions anticipated for a primary alkyl amine, such as acylation and protonation. Reaction with sulfuryl chloride followed by oxidation of the sulfonamide give diethyldiazene, EtN=NEt. Ethylamine may be oxidized using a strong oxidizer such as potassium permanganate to form acetaldehyde.