There is an urgent need for faster, brighter, and more controllable scintillation materials in advanced nuclear medicine, high-energy physical experiments, and dark matter particle detection. Nevertheless, the trade-off between high emission efficiency and fast timing characteristics remains a common challenge in the entire optical field. To address this issue, we develop a composition engineering strategy that involves multisite selective doping. This strategy aims to transform nearly all Ce 3+ into fast-emitting Ce 4+ while synergistically suppressing the electron traps. Even at very low doping concentrations, the designed Ca 2+ , Al 3+ , and Ce 3+ tridoped oxyorthosilicate exhibits a scintillation decay (τ d ) acceleration of 20%, accompanied by a 25% increase in light yield (LY). The ratio of emission efficiency and timing characteristics (LY/τ d ) can be enhanced by 56%, which realizes the perfect balance of high LY and fast τ d . Our work provides a method for designing efficient, ultrafast, and controllable scintillators in multicomponent systems, thus paving the way for high-resolution radiation detection and imaging applications.