Corrosion by ammonia/amine salts in hydrocarbon streams such as distillation overhead streams that contain a mineral acid and water can be prevented, avoided or minimized by adding certain strong amines to the streams. The amines have a pKa between about 10.5 to about 12 and include, but are not necessarily limited to, dimethylamine, diethylamine, dipropylamine, diisopropyl-amine, di-n-butylamine, diisobutylamine, di-sec-butylamine, di-tert-butylamine, pyrrolidine, piperidine, and combinations thereof. If the hydrocarbon stream further includes a nitrogen-containing compound such as ammonia, a tramp and/or a residual amine which can form a corrosive salt with the mineral acid, then the added amine is a stronger base than the tramp or residual amine, if present. The amount of added amine is greater than total amount of nitrogen-containing compound, so that any corrosive salts formed are less corrosive than the salts that would otherwise form from the ammonia and/or tramp amine.