We investigated the effects of low temperature on the expression of mitochondria-encoded genes in wheat. During the course of our study, we found that the transcriptional pattern of cox2 was affected by low temperature. Northern blot analysis indicated that the precursor transcript before intron splicing was clearly increased by cold, although the level of mature message was not changed. We also found that cold treatment severely suppressed RNA editing at intron-binding site I of the precursor transcript, which plays an important role in intron splicing. These results suggest that low temperature could affect the post-transcriptional regulation of wheat mitochondrial cox2 transcripts, i.e. intron splicing and/or RNA editing.