Abstract:The result of southern hybridization showed that the rice chloroplast genome can encode its own RNA polymerase. The α subunit gene fragment of this enzyme has been cloned into E. coli plasmid pUC 19. By deletion method and dideoxynucleotide chain termination, we analysed its nucleotides sequence. This gene consists of 337 codons. It reserves a high homology between rice, monocotyledonous plant and tobacco, dicotyledonous.