The development status and existing problems in the field of nuclear agricultural sciences (NAS) are reviewed .Including the application of nuclear technology in mutation breeding by irradiation, isotopic technique application, food irradiation and sterile insect technique, etc. China has made great achievements in the research and application of nuclear technique in agriculture from 1950s to 1990s. Due to lack of enough financial support to the basic research and reformation of science & research system in China, the development of NAS now meets its tough time. Through analyzing the difference and reasons of NAS development between China and the USA, it is recognized that the innovation in research and scientific system is important for promoting the development speed and research level of NAS.