Abstract: A portable uranium enrichment measurement apparatus for nuclear fuel assembles with CdZnTe detector system was set up. In the experiments, several kinds of nuclear fuel assemble were measured. Therefore, a NDA method to measurement uranium enrichment using CZT detector was set up. The relative error of measurement results is less than 3%, the measurement method is simple, and the apparatus is portable and reliable. It can be used in nuclear materials safeguards verification measurements.