Potassium niobates partially substituted with titanium, KNbXTi1-XO3 (x = 1.0, 0.8, 0.6, 0.5) with perovskite type-structures were synthesized by the citrate method, fully characterized and evaluated for their photocatalytic performance in the degradation of Methyl Orange (MO) dye by UVA–vis light illumination. For the titanium substituted perovskites a slight decrease in the band-gap values compared to the non-substituted KNbO3 was observed. After 240 min under irradiation the decoloration efficiency of MO assays reached values higher than 65%. The highest photocatalytic performance for MO decoloration of KNb0.6Ti0.4O3 was attributed to the decrease in the band-gap value, crystal size and the crystalline perovskite structure, indicating a simple strategy for synthesizing active photocatalytic materials.