To provide a method for producing a resorcinol/formaldehyde/aliphatic ketone resin useful as adhesives.

A method for producing a resorcinol/formaldehyde/aliphatic ketone resin is provided which reacts a resorcinol, formaldehydes, and a 3-6C aliphatic ketone, in the presence of water, salt, and an acid catalyst, and as necessary, in the presence of an organic solvent inactive for the reaction. The production method including the following four steps is also provided: (a first step) a step of reacting resorcinol, formaldehydes, and a 3-6C aliphatic ketone, in the presence of water, salt, and an acid catalyst, and as necessary, in the presence of an organic solvent inactive for the reaction, (a second step) a step of neutralizing the reaction liquid obtained in the first step with an alkali, (a third step) a step of separating the reaction liquid obtained after the neutralization in the second step into an organic phase and aqueous phase, (a fourth step) a step of concentrating the organic phase obtained after the separation in the third step.