The terminator technology produces seeds not to germinate in the next generation. X-ray crosscomplementing group 3 (AtXRCC3) is a protein involved in DNA repair and recombination in Arabidopsis. A knock-out Arabidopsis line for AtXRCC3 inserting T-DNA on a position of 703 bp downstream from the start codon was identified. The homozygous line of AtXRCC3 is morphologically similar to the heterozygous line and wildtype of Arabidopsis until flowering. However the homozygous line did not set seeds in siliques showing sterility. These results suggest that AtXRCC3 is essential for meiosis in plant seed development and is useful as a terminator gene in plants.