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Aquaporin(AQP)efficiently transports the water molecule in the membrane structure and it belongs to the membrane intrinsic protein(MIP)super family.Before AQP was discovered it was widely believed that the free diffusion was the only way by which the H2O molecules influxed and effluxed of the cell membrane,until the first AQP was discovered by Agres team in 1988.After that,kinds of AQPs were isolated in animals,plants,fungi,bacteria and so on.In higher plants the AQP was found involved in the drought or salt tolerances.In this study,two AQP genes from Brassica napus,one of the most important oil crops in China,were isolated.They were BnPIP3-like and BnMOD.The full lengths of cDNAs of the two genes were cloned by using the specific primers designed according to the sequences from Arabidopsis thaliana and then sequenced.The BnPIP3-like gene had 846 bp in lengh and the deduced amino acid sequence contained 281 amino acid residues,which shared 91.7%and 95.3%identity with the nucleotide sequence and amino acid sequence of PIP3 gene from Arabidopsis,respectively.Prediction of transmembrane helices in proteins showed that the BnPIP3-like contained 5 loops and 6 transmembrane α helixes.Highly conserved Asn-Pro-Ala regions were found in loop B and loop E.While the BnMOD was also found containing 5 loops and 6 transmembrane α helixes,with more than 90%identity with the nucleotide sequence and amino acid sequence of homologous gene from Arabidopsis.And the phylogentic trees were established.These results showed that the two genes had the classical structure of AQP and were new members of the AQP families.The eukaryotic expression vector were constructed using the restriction sites and would be used in functional analysis in the future research.