Traarent ceramics are a bunch of materials that have always been challenged due to the need for high technology. These materials are replaced by glass (as traditional optical materials) because of their high mechanical strength and high hardness. In recent years, traarent ceramics have attracted many researchers. The main uses of this category of ceramics include lasers, cutting tools, traarent valves and night vision devices. Traarent ceramics are divided into two types of single crystals and polycrystals. In optics, traarency is a feature that allows light to pass through. The factors affecting ceramic traarency include porosity, multiple phases, grain size, fuzzy distribution, and variation in the refractive index of different phases. Magnesia is a white mineral substance with an energy gap of 8/7 and a refractive index of 1.64. Iteria is the most famous combination of yttrium with a bcc cubic crystalline structure and a bonded bond energy of 5.8 and a refractive index of 1.8428. NiO has a crystalline structure of salt with a refractive index of 18.2 and a graft bond energy of 4-4 / 3 ev. The production of traarent ceramics, Y 2 O 3 -MgO, has been performed, but with increasing thickness, the traarency sample disappears. The presence of NiO in MgO causes the change in its optical refractive index and can be controlled by controlling the percentage of NiO, reducing the refractive index of MgO to Y 2 O 3 . By adding some NiO, the difference in refractive index can be reduced by two phases and increased traarency. In this study, the synthesis of Y 2 O 3 -NiO powder was investigated by sol-gel method with various percentages of NiO to investigate NiO's effect on Y 2 O 3 . To synthesize this composite, ethylene glycol and citric acid were used to control particle size. Then, the synthesis of Y 2 O 3 -NiO-MgO nanocomposite was carried out using sol-gel method with ethylene glycol and citric acid. Both composites were calcined after synthesis at 1000 ° C, and also Y 2 O 3 NiO powder was poured into tablets after calcination and sputtered at 1400 ° C. X-ray diffraction, differential pressure thermochemical tests, visible-ultraviolet spectroscopy and photoluminescence spectroscopy analysis of each compound were investigated, and it was observed that in the NiO Y 2 O 3 composite, no change in nickel ion exchange was observed in Yttria. The same conditions apply to the synthesis of Y 2 O 3 NiO-MgO composites. In a Y 2 O 3 - NiO-MgO synthesized nanocomposite, nickel substitution in magnesia was observed and then composited with iteria. key words Traarent ceramics, Y 2 O 3 - NiO-MgO -, refractive index