The optical properties of Al-doped SmFeO 3 (SmFe 1−x Al x O 3 , for x varying from 0 to 0.15), were monitored by diffuse reflectance spectroscopy (DRS). The diffuse reflectance spectra were used to study the surface properties of the samples. The DRS spectra exhibit three reflection bands at different regions. The product was characterised by X-ray diffraction to confirm the formation of single-phase crystals of the perovskite structure. The bandgap, a major factor in determining the optical performance of any material, was found to be tunable with Al content (x).