Abstract: The genome-wide identification of the ribosome-inactivating protein family genes in 34 representative plant species with the genome data were performed.The different taxa was analyzed,the possible way of amplifications and the functional differentiation wereestimated, and the general evolution trend of the RIP gene family in plants was discussed. A total of 79 RIP gene family members were identified by BLAST and HMMSearch method. Through the sequence alignment and construction of the phylogenetic tree, it was found that RIPs had dual origins in the monocotyledons, and RIPs existed before the differentiation of the dicotyledons and monocotyledons.It is obtained that they maybe appeared in the early terrestrial plants in order to adapt the complex environment, then expansion of the spectrum and loss of the copies are happening during the long term evolution, finally survived in different plants through the functional differentiation.