In this paper, Y-type strontium hxaferrite (Sr
2Co
2Fe
12O
22) nanostructure with molar ratio of citric acid to metal nitrats of 1:0.5, 1:1, 1:1.5 and 1:2 prepared using a sol-gel of auto-combustion method and then prepared powders were sintering at 1000
˚C for 3 h. In order to investigate structural, magnetic and dielectric properties of the Sr
2Co
2Fe
12O
22 nanostructure, samples have been analyzed by X-ray diffraction analysis (XRD), Fourier transforms infrared spectroscopy (FT-IR), scanning electron microscopy field emission (FESEM) , vibrating sample magnetometer (VSM) and LCR meter methodes. The results of measurements of structur show that Y-type hexaferrite structural in the samples with molar ratios of 1.5 and 2 was completely formed, so that in the sample with molar ratio of 1.5 peaks and its intensity is closer to the standard card. Also, the results of dielectric reveal that by increasing frequency, dielectric constant and dielectric loss decreases which indicates that samples could be suitable for use in devices. The results show that the best papered sample is at temperature and time of 1000