Abstract: The full length coding sequence of AtHKT1 was cloned via RT-PCR (reverse transcription-polymerase chain reaction) from the leaves of Arabidopsis thaliana seedling under NaCl stress. The full-length cDNA contained 1521 bp and encoded a polypeptide of 506 amino acids and a termination codon. The sequence shared 99.34% homology with the reported sequence (accession number AF237672), but the homologies were very low compared with similar genes from other plants. The gene was submitted to GenBank and was given the registration number AY685182. Bioinformatics softwares were used to predict and analyze the protein function and structure of the AtHKT1 gene cDNA sequence. The molecular weight of the deduced polypeptide of AtHKT1 was 57.45 kD. The theoretical pI was 9.33. The N-terminal amino acids from 1 to 40 formed a classic signal peptide sequence. The peptide from 152 to 500 was a Trk H cation transporter conserved domain. It might also carry protein kinase C, tyrosine kinase, cAMP-and cGMP-dependent protein kinase phosphorylation, glycosylation, N-myristoylation sites and other function sites. The deduced peptide contained 10 transmembrane domains. The transmembrane domains near the N-terminus, the C-terminus and the middle part of the peptide displayed high hydrophobicity. Therefore, it is suggested that the gene product of AtHKT1 might play roles in facilitating cation transportation.