In this study, zinc ferrite nanoparticles, which has an important place among the spinel ferrite structured nanomaterials due to its unique properties, were synthesized by microwave-assisted combustion method and later were used as photocatalysts in the removal of dyestuffs by photocatalytic degradation method from wastewaters of textile industry. In the synthesis studies, it was determined that the microwave effect alone was not sufficient to complete the transformation. Heat treatment application is envisaged to solve this problem and in order to determine the optimum heat treatment temperature, the sample produced by microwave effect were subjected to heat treatment at 300℃, 400℃, 500℃, 600℃, 700℃, 800℃ and 900℃, respectively. It has been observed that the heat treatment has a significant effect on the crystal structure of the particles and 700℃ has been determined as the optimum heat treatment temperature. The data obtained showed that, under these conditions, the zinc ferrite nanoparticles were successfully synthesized and the powder produced completely consisted of nano-sized particles. Moreover, results showed that the synthesized zinc ferrite nanoparticles has a saturation magnetization value sufficient to separate them from the aqueous medium. Finally, zinc ferrite nanoparticles produced under optimum conditions were used as photocatalysts in the removal of textile dye known as Procion Yellow HE-3G from wastewater by photocatalytic oxidation. In photocatalysis experiments, it was observed that synthesized zinc ferrite nanoparticles provided very high removal efficiencies as photocatalysts and almost all of the dye content in the solution could be removed.