The discharge of effluents containing uranium (U) ions into aquatic ecosystems poses significant risks to both human health and marine organisms. This study investigated the biosorption of U(VI) ions from aqueous solutions using corncob-sodium alginate (SA)-immobilized Trichoderma aureoviride hyphal pellets. Experimental parameters, including initial solution pH, initial concentration, temperature, and contact time, were systematically examined to understand their influence on the bioadsorption process. Results showed that the corncob-SA-immobilized T. aureoviride hyphal pellets exhibited maximum uranium biosorption capacity at an initial pH of 6.23 and a contact time of 12 h. The equilibrium data aligned with the Langmuir isotherm model, with a maximum biosorption capacity of 105.60 mg/g at 301 K. Moreover, biosorption kinetics followed the pseudo-second-order kinetic model. In terms of thermodynamic parameters, the changes in Gibbs-free energy (ΔG°) were determined to be −4.29 kJ/mol at 301 K, the changes in enthalpy (ΔH°) were 46.88 kJ/mol, and the changes in entropy (ΔS°) was 164.98 J/(mol∙K), s. Notably, the adsorbed U(VI) could be efficiently desorbed using Na2CO3, with a maximum readsorption efficiency of 53.6%. Scanning electron microscopic (SEM) analysis revealed U(VI) ion binding onto the hyphal pellet surface. This study underscores the efficacy of corncob-SA-immobilized T. aureoviride hyphal pellets as a cost-effective and environmentally favorable biosorbent material for removing U(VI) from aquatic ecosystems.