Abstract A chiral symmetry-breaking reaction model was constructed based on the Oregonator model, which was proposed to explain the oscillatory behavior of the Belousov–Zhabotinskii reaction by Field, Körös, and Noyes. Its symmetry-breaking transition results in the dominance of one enantiomer, and the disappearance of the other. Depending on the parameter values, an asymmetric steady state, symmetric steady state, or oscillatory behavior with either the same or different amplitudes is exhibited. Numerous chemical oscillation systems have been previously reported, and these systems always include autocatalytic processes. Accordingly, if the autocatalyst in these experimental systems has optical isomers and each isomer catalyzes its own production, the spontaneous appearance of a chiral symmetry-breaking state is expected in the chemical oscillation system under the appropriate experimental conditions.