In this work, Ce-YIG nanoparticles with nominal composition of Y_3-xCe_xFe₅O₁₂
(x = 0, 0.1, 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) were first fabricated by sol-gel method and then the influence of the cerium substitution on the structural and magnetic properties of garnet nanoparticles were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared (FT-IR) spectroscopy, vibrating sample magnetometer (VSM) and mössbauer spectroscopy. The XRD results showed that the maximum amount of the Ce³⁺ substitution in YIG structure is x = 0.6. Magnetic measurement shows that room temperature saturation magnetization   of nanoparticles increases up to x = 0.3 firstly and then decreases by increasing Ce content. The variation of saturation magnetization can be explained according to mössbauer studies. The mössbauer analysis showed that due to Ce substitution a and d sublattice split into two pairs of distorted and undistorted sublattice. So reduction in saturation magnetization is disscused.