Large scale cadmium sulfide nanoparticles were synthesized by simple chemical route. The microstructure of cadmium sulfide nanoparticles was characterized by X-ray diffraction pattern (XRD) FESEM, FTIR and UV-visible spectroscopy. The XRD results showed that there was a transformation from cubic to hexagonal crystalline phase. The W–H plots show the size and nature of the strain incorporated in peak broadening of X-ray diffraction peaks. Some of the observed peak broadening can be attributed to crystallite size and microstrain effects, dislocation density, hkldependent peak broadening and peak shifts are clearly associated with stacking faults. The refractive index of the CdS nanoparticles was estimated to 2.22. The optical band gap of the synthesized CdS nanoparticles was calculated by Tauc relation and found to be 3.45 eV. The dependence of the blue shift and optical band gap on the quantum size effect was confirmed by UV-Visible spectroscopy. FTIR study confirmedthat the –C–O and –OH groups of thioglycerol can readily bind with CdS nanoparticles.