The present invention provides a radiation curable resin composition and method of production therefor; the present composition has wide applications as an ink, coating or the like, is dilutable in water or an organic solvent, and forms a coating which has excellent hardening characteristics and adherence to a substrate, as well as superior resistance to heat, chemicals and boiling, this resin composition may be redissolved with water or an organic solvent prior to hardening; which have a number average weight of 500 to 50,000, characterized in that the aprotic ammonium salt represented by general formula 1 is contained in the resin in the amount of 0.1 to 4.0 mol/kg. ##STR1## (In the formula, X is an organic group which is bound to the main chain and includes a hydrocarbon of 0 to 3 carbon atoms, an ester and an amide; R1 and R2, which may be the same or different, represent a hydrocarbon of 1 to 8 carbons which may be substituted with a hydroxyl group, ester group, alkoxy group or halogen atom, wherein R1 and R2 may bond together, with bonding occurring between the nitrogen atoms of R1 and R2 to form a heterocyclic ring; R3 indicates a hydrogen atom or a hydrocarbon of 1 to 18 carbon atoms that has one or more polymerizable unsaturated double bonds and may be substituted with a hydroxyl group, ester group, alkoxy group, or halogen atom; and R4, R5 and R6, which may be the same or different, represent a hydrogen atom or a hydrocarbon of 1 to 18 carbons which may be substituted with a hydroxyl group, ester group, alkoxy group, or halogen atom, wherein R5 and R6 may bond together to form a heterocyclic ring.)