In the context of americium recycling, the Minor Actinides Bearing Blanket (MABB) concept is being considered, involving the use of advanced fuel U-substituted Am2O3 with a cubic structure for the heterogeneous transmutation of americium.Considering Nd2O3 as a substitute for Am2O3, a series of Nd3+-substituted UO2 samples with the general formula U1-xNdxO2±δ (0.1 ≤ x ≤ 0.4, δ ≥ 0) were obtained using a sol-gel based process (Complex Sol-Gel Process).These oxides, in the form of microspheres, were prepared through a method applied at the ICHTJ, involving sintering under reducing conditions up to 1200 °C for 4 h.The influence of neodymium was analyzed, and the structural properties were associated with the fabrication method.The crystalline phases, structure, and particle morphol. of the samples were determined through X-Ray Diffraction (XRD), High-Temperature X-Ray Diffraction (HT-XRD), X-Ray Fluorescence (XRF), SEM (SEM) with Energy Dispersive Spectroscopy (EDS), Thermogravimetry DTA (TG-DTA), Fourier-Transform IR Spectroscopy (FTIR) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS).The structural analyses proved the presence of U1-xNdxO2±δ single-phase solid solutions for all types of sintered Nd-doped microspheres.The lattice parameter determined for the single-phase solid solutions decreased with dopant content.The morphol. characterization revealed that the UO2 microspheres with Nd3+ showed no significant differences regardless of the amount of additive, and maintained their integrity during the selected thermal treatment conditions.The methodol. and conditions used in this study are consistent with the development of strategies for producing UO2 transmutation fuel containing Pu and/or minor actinides.