Zinc oxide was synthesized from zinc sulphate using different reducing agents under microwave irradiation. The influence of sodium borohydride, hydrazine hydrate and urea on the shape and size of the products were investigated by scanning electron microscopy(SEM) and X-ray diffraction(XRD). SEM showed the nano-sized spherical and rectangular shaped structures in case of sodium borohydride and hydrazine hydrate, whereas micro-sized hexagonal structures were formed in case of urea under the same irradiation power. The reducing agents played an important role in forming the various structures. Thus different shapes and size of structures were produced by only varying the reducing agent, which had wide applications in various fields. Zinc oxide was synthesized from zinc sulphate using different reducing agents under microwave irradiation. The influence of sodium borohydride, hydrazine hydrate and urea on the shape and size of the products were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) . SEM showed the nano-sized spherical and rectangular shaped structures in case of sodium borohydride and hydrazine hydrate, while micro-sized hexagonal structures were formed in case of urea under the same irradiation power. The reducing agents played an important role in forming the various structures. Thus different shapes and size of structures were produced by only varying the reducing agent, which had wide applications in various fields.