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In the present study, using <i>Aspergillus niger</i> and <i>Penicillium tricolor</i>, the influence of the selected parameters, including sucrose concentration, inoculation size of spores, pulp density, and pre-culture time, on the bioleaching efficiency (biomass, organic acids production, and vanadium extraction, respectively) of red mud were studied. The bioleaching kinetics under optimal conditions were also explored. Sucrose concentration showed a positive linear effect on bioleaching efficiency below 143.44 and 141.82 g/L using <i>A. niger</i> and <i>P. tricolor</i>, respectively. However, a higher concentration was unfavorable for vanadium extraction. The inoculation size of spores showed an insignificant effect on both biomass and vanadium extraction if it exceeded the lowest coded levels (0.5 &#215; 10⁷/mL). Red mud pulp density showed a negative effect on the bioleaching efficiency of <i>A. niger</i> but a positive effect on organic acids production and vanadium extraction of <i>P. tricolor</i>. A pre-culture was indispensable for <i>A. niger</i> but not for <i>P. tricolor</i> due to the fact of its isolation from the red mud examined in this study. The kinetics analysis showed that the leaching rate of vanadium followed a two-domain behavior: initially, a rapid leaching period of approximately 10&#8722;15 days and, subsequently, a slow leaching period. Considering the change of the particles&#8217; appearance as well as in the elemental composition of the bioleached red mud, it is speculated that the rate of leaching agents through the silicon minerals was the rate-limiting step of dissolution kinetics under the fungal bioleaching process.