Magnetic NiFe2O4 nanoparticle (NFNPs) was synthesized by the microwave-assisted method using Tamarindus indica seeds as a green reducing agent. The identification of NFNPs was carried out by XRD, FTIR, SEM with EDAX analysis, UV-Visible Spectroscopic and luminescence techniques. Spinel structure of NFNPs with a single phase has been confirmed by XRD with an average crystallite size of 21 nm. FTIR confirms the presence of tetrahedral and octahedral sites of prepared NFNPs. SEM with EDAX and TEM gives the information of agglomeration of magnetic nanoparticles with elemental composition present in the NFNPs and spherical nature of nanoparticles with a particle size of 29 nm. The prepared NFNPs are visible active with band gap of 1.92 eV. NFNPs show effective photocatalytic activity under visible light irradiation towards the degradation of anionic Alizarin red S dye and cationic Methylene Blue dye. NFNPs show good magnetic property in VSM studies. The prepared NFNPs can be useful for wastewater treatment.