Microwave synthesized nano-sized Cu₂ZnSnS₄ (CZTS) powder was irradiated with 6 MeV electrons, to investigate stability under radiation. The structural, optical, vibrational and morphological properties were explored using X-ray diffraction, UV–Visible spectroscopy, Raman spectroscopy and scanning electron microscope (SEM). The irradiated sample shows significant change in properties when compared with the pristine sample. X-ray peak broadening analysis has been used to estimate the crystallite size and lattice strain. Raman spectroscopy analysis confirms the transition of ordered kesteriteto disordered kesterite phase after electron irradiation at electron fluence of 4 x 10¹⁵ e^-/cm². CZTS nanoparticles having hierarchical flower-like morphology starts agglomerating after electron irradiation as observed from SEM images. The sample did not amorphize up to the highest fluence 4 x 10¹⁵ e^-/cm² employed in this study.