Ultra-high-performance concrete (UHPC) shows great promise for protective structures against weapon strikes, and hybrid steel fibers are frequently incorporated to enhance its mechanical performance. To evaluate the effect of fiber hybridization on the ballistic resistance of UHPC, a mesoscale-based analysis method was developed with the considerations of explicit representation of random steel fibers and the equivalently modeling of fiber-matrix interaction. The developed method was validated through a series of quasi-static and dynamic mechanical tests, including uniaxial compression and tension tests, split Hopkinson pressure bar tests, and dynamic spalling tests. Additionally, numerical simulations of the projectile penetration test on UHPC target demonstrated that the method effectively captures the fiber bridging effects on the dynamic responses and failure patterns of UHPC target. Finally, quantitative studies were conducted to evaluate the impact of steel fiber hybridization-considering both long and short fibers, as well as straight and hooked fibers-on the projectile resistance of UHPC. The results revealed that the fiber hybridization, combining short/long or straight/hooked fibers, had a greater effect on the cratering damage and a slight impact on the depth of penetration of UHPC targets under projectile impacts. Moreover, the incorporation of 0.5% short and 1.5% long fibers, as well as 0.5% straight and 1.5% hooked fibers exhibit the most excellent ballistic resistance.