Abstract: In order to evaluate the performance of the fuel elements, which were produced for the 10 MW high temperature gas-cooled reactor(HTR-10), the irradiation test of two spherical fuel elements sampled randomly from the first and second product batches, respectively, was performed in an irradiation facility with in-pile gas loop of the Russian IVV-2M research reactor. The temperature of the fuel element in each irradiation capsure and release of gas fission products from the irradiated fuel element can be controlled and measured, respectively. The post-irradiation examination(PIE) contains visual inspection, dimension measurement for the irradiated fuel element, determining the distribution of the solid fission products in the matrix graphite along the ball diameter, measuring the failure fraction of the loose coated fuel particles obtained from the ball deconsolidation, ceramography examination of the failed and intact particles. The PIE results show no any failure of coated fuel particles was induced by the irradiation and the produced fuel element can meet the design requirement of HTR-10.