In this study, aluminum ion (Al³⁺) substituted yttrium iron garnet nanoparticles Y₃Al_xFe_5-xO₁₂ (x = 0.0, 0.2, 0.4) were fabricated by the sol-gel method. X-ray diffraction (XRD) patterns confirmed the pure garnet structure for all samples. The chemical bonds and the garnet phase were studied by using FT-IR, Far-FTIR. The cation distribution and the magnetic hyperfine parameters were obtained by MÖssbauer spectroscopy and confirmed the VSM results. The results of vibrating sample magnetometer (VSM) show that saturation magnetization decrease with increasing aluminum ion concentration. These changes assigned to the Neel theory and the spin canting due to the reduction of superexchange interactions between iron ions in the octahedral and tetrahedral and octahedral sites.