The development of high-performance metal-free organic X-ray scintillators (OXSTs) is challenging due to the need for robust X-ray absorption, efficient exciton utilization, and short luminescence lifetimes. This study presents a strategy using halogenated open-shell organic radical scintillators to enhance X-ray scintillation. The synthesized scintillators, TTM-ICz and TTM-ICzBr, exhibit strong X-ray absorption, efficient X-ray stability, and theoretical 100% exciton utilization efficiency with a short lifetime of ~18 ns. These organic radicals show superior X-ray scintillation performance, suitable for X-ray radiography and high-resolution micro-CT imaging. The study demonstrates the potential of organic radicals as promising candidates for OXSTs, offering valuable insights and a roadmap for advanced organic radical scintillators. The research highlights the advantages of metal-free organic scintillators, including abundant source materials, ease of processing, low cost, and high mechanical flexibility, making them a promising alternative to inorganic scintillators.The development of high-performance metal-free organic X-ray scintillators (OXSTs) is challenging due to the need for robust X-ray absorption, efficient exciton utilization, and short luminescence lifetimes. This study presents a strategy using halogenated open-shell organic radical scintillators to enhance X-ray scintillation. The synthesized scintillators, TTM-ICz and TTM-ICzBr, exhibit strong X-ray absorption, efficient X-ray stability, and theoretical 100% exciton utilization efficiency with a short lifetime of ~18 ns. These organic radicals show superior X-ray scintillation performance, suitable for X-ray radiography and high-resolution micro-CT imaging. The study demonstrates the potential of organic radicals as promising candidates for OXSTs, offering valuable insights and a roadmap for advanced organic radical scintillators. The research highlights the advantages of metal-free organic scintillators, including abundant source materials, ease of processing, low cost, and high mechanical flexibility, making them a promising alternative to inorganic scintillators.