a b s t r a c t ZnSe nanoparticles were synthesized for the first time by a microwave heating process using high purity Zn and Se powders in equimolar ratio. Nanoparticles of the title material were obtained within 30 min with high crystallinity. The crystalline phase of the synthesized ZnSe nanoparticles was confirmed by powder X-ray diffraction (PXRD), the crystallite size was calculated using Scherrer's formula and found ∼33.14 nm. A scanning electron microscope (SEM) also used to determine the size of the nanoparticles which shows an average particle size of ∼50 nm, in agreement with PXRD. The particle size distribution was in the range of ∼40 to 60 nm. The Raman spectra have been recorded at ambient temperature, TO and LO phonon modes were observed at ∼208 and ∼253 cm −1 in the ZnSe nanoparticles which showed a clear shifting toward the low frequency relative to bulk values. The optical study was investigated by UV-Vis. Spectroscopy, the optical energy band gap of the synthesized nanoparticles was calculated and found to be 2.99 eV higher than bulk ZnSe (E g = 2.7 eV) which shows the clear blue shifting by 0.29 eV which may be due to the crystallite size and energy gap confinement.