Manganese and iron doped cadmium gallate has been synthesized by sol–gel approach. PXRD pattern shows the cubic arrangement of cadmium gallate spinel. Raman spectrum concludes the complete structural analysis of undoped and doped samples. Additionally, morphology and elemental ratio is obtained using FESEM and EDS spectroscopy. Blue indigo and green emission bands are shown in photoluminescence spectra. An excellent antiferromagnetic and ferromagnetic behavior of manganese and iron doped cadmium gallate are shown in the magnetic study. Low band gap of doped samples has made this material as a prominent catalyst for the degradation of methylene blue dye when exposed to UV–visible irradiation.