Salinity is one of the major abiotic stresses which adversely affect crop plants limiting growth and yield potential. In the present study, a salt induced sos101 gene from Arabidopsis thaliana (Atsos101) which encodes WD40 repeat containing protein has been identified. Furthermore, four candidate orthologues of Atsos101 gene in rice (Ossos101) have also been identified by database searching. Salt responsive temporal gene expression was analyzed by quantitative real-time RT-PCR for the candidate orthologues in three rice genotypes with differing salt tolerance at two different salt concentrations (50 mM and 100 mM NaCl). In order to understand the evolutionary relation between the Arabidopsis sos101 gene and its orthologues from rice and other crop plants a phylogenetic analysis was performed. Analysis of the amino acid sequence revealed highly conserved WD40 repeat domain in SOS101 protein and its orthologues in rice. This study revealed the salt inducible regulation of WD40 repeat proteins in both Arabidopsis and rice.