The multi-scale related models for the effective elastic constants of porous U-10Mo fuels under the irradiation conditions are developed with the proposed multi-level homogenization method. The grain recrystallization effects are taken into account, with fission gas bubbles (FGBs) distributed in the external bubble-contained region of Representative Volume Element (RVE). Performing theoretical analysis and numerical simulation, the effective elastic performances are firstly obtained for the bubble-contained region, and then are volumetrically averaged with those of the internal no-bubble region. The effective elastic constants of irradiated U-10Mo fuels determined in this study agree well with some available experimental data in the references. The research results indicate that: (1) the effective elastic constants of porous U-10Mo fuels are hardly affected by the pore pressure, mainly depending on the macroscopically average porosity; (2) the theoretically derived model for the effective bulk modulus is the same as the degraded Mori-Tanaka model, with the inclusion phase there regarded as bubbles having zero elastic constants. The developed models correlate the elastic constants of irradiated U-10Mo fuels with their continuously varying porous structures, which lay a foundation for modeling the multi-scale irradiation-induced thermo-mechanical coupling behaviors.