The present invention relates to an additive composition for scavenging hydrogen sulfide in hydrocarbons, wherein said additive composition comprises a combination of (a) glyoxal and (b) at least one aliphatic tertiary amine or oxide treated derivative thereof, or a mixture of the aliphatic tertiary amine and the oxide treated derivative thereof. In one embodiment it also relates to a method for scavenging hydrogen sulfide in hydrocarbons, and in another embodiment it relates to a method of using an additive composition of the present invention for scavenging hydrogen sulfide in hydrocarbons. In yet another embodiment it relates to a composition for scavenging hydrogen sulfide in hydrocarbons comprising (A) a hydrocarbon and (B) a hydrogen sulfide scavenging additive composition of the present invention.