Abstract: Radiation technology has been widely studied and applied in synthesis of nanocrystal materials due to its unique advantages of cleanliness, economy, efficiency and industrialization potential. In current, it's reported that that carbon nanocomposites, metal/alloy nanocrystals and metal oxide nanocrystals have been successfully prepared by using γ ray, high energy electron beam or ion beam. Moreover, the morphology, size, surface functional groups and monodisperse properties of nanoparticles can be regulated by adjusting radiation dose, dose rate, stabilizer, interface environment and radical trapping agents. Therefore, the review will focus on the research and application of radiation technology in synthesis of carbon-based nanomaterials, metal/alloy nanocrystals and semiconductor nanocrystals. Based on the review, the future application and new direction of radiation technology in the regulation and synthesis of new nanocomposites are prospected, which will promote the development and application of nanocrystal composites in medical imaging, drug delivery, environmental protection, optoelectronic devices and energy.