Single-crystalline YFeO₃ particles with the perovskite structure have been fabricated through a facile KCl-assisted solution combustion synthesis (SSCS) method, using alanine as a fuel and corresponding nitrates as oxidants. The effects of the fuel-to-nitrate ion (F/N) and the KCl-to-metal ratios (KCl/M) on the phase and microstructure of the products are studied in detail by X-ray diffraction analysis, scanning electron microscopy, low temperature N₂ adsorption, UV–visible diffuse reflection spectroscopy. It is remarkable that the introduction of KCl into the solution combustion synthesis (SCS) process results in a dramatic increase in surface of the obtained YFeO₃, i.e. a more than sixth-fold increase from 2.9 to 19.6 m²/g when F/N = 0.30 and forty-fourth-fold increase from 0.5 to 24.2 m²/g in the case of F/N = 0.33. Results show that both of YFeO₃ nanoparticles prepared by SCS and SSCS exhibit excellent photocatalytic activity for the photodegradation of rhodamine B in the presence of H₂O₂. The photo-generated holes (h⁺) and •OH were the main active species of YFeO₃ for RhB degradation under visible light irradiation.