Chemical doping is an important method to introduce new flux pinning centers in high-temperature superconductors. RE₂Ba₄CuMO_y (REM-2411, where RE is a rare-earth element, and M = Nb, W, Sb and Bi etc.) phase has been widely investigated in recent years because of its chemical stability and spontaneous formation of REM-2411 nanoparticles in the RE-Ba-Cu-O (REBCO) superconducting matrix. Using metallic oxide doping to in-situ form REM-2411 in REBCO is a more simple and efficient method. In this article, the effects of nanosize Bi₂O₃ and Sb₂O₃ doping on the growth and properties of Y-Ba-Cu-O (YBCO) bulk superconductors are investigated using the 011-type infiltration growth technique. The compositions of Y₂O₃+1.15BaCuO₂+0.1CuO and Y₂O₃+10BaCuO₂+6CuO are used as solid source and liquid source respectively. The nanopowders are doped in the solid source pellet. It is found that the normal growth of YBCO bulk is not affected by the weight percent of 0.5% nano-Bi₂O₃, and the sample exhibits enhanced levitation force property and higher J_c property. The size of the introduced YBi-2411 nanoparticles is mainly below 100 nm. While for the weight percent of 0.5% nano-Sb₂O₃, the sample exhibits a much smaller growth region containing periodic macrosegregated bands, and both the levitation force and J_c are significantly reduced. X-ray diffraction (XRD) results for samples with a high doping level (weight percent of 5%) confirm the existence of the YBi-2411/YSb-2411 phase in the nanosize Bi₂O₃/Sb₂O₃-doped sample. Scanning electron microscopy (SEM) results indicate that large amounts of YBi-2411 nanoparticles (approximately 200 nm) with very high density are observed in the weight percent of the 5% nano-Bi₂O₃ doped sample, indicating that in situ formation of YBi-2411 nanoparticles in the YBCO regime occurs readily. Taking into account both the doping effect on the growth and superconducting properties, nano-Bi₂O₃ can be considered a safe and superior dopant for the YBCO bulk superconductors, and also has the potential to serve as a universal route for enhancing the properties of all the REBCO superconductors. The results of this study are important for further increasing the performance of the YBCO bulk superconductors.