Three Lactobacillus-like strains, NB53T, NB446T and NB702, were isolated from traditional fermented food in Thailand. Comparative 16S rRNA gene sequence analysis indicated that these strains belong to the Lactobacillus plantarum group. Phylogenetic analysis based on the dnaK, rpoA, pheS and recA gene sequences indicated that these three strains were distantly related to known species present in the L. plantarum group. DNA-DNA hybridization with closely related strains demonstrated that these strains represented two novel species; the novel strains could be differentiated based on chemotaxonomic and phenotypic characteristics. Therefore, two novel species of the genus Lactobacillus, Lactobacillus plajomi sp. nov. (NB53T) and Lactobacillus modestisalitolerans sp. nov. (NB446T and NB702), are proposed with the type strains NB53T ( = NBRC 107333T = BCC 38054T) and NB446T ( = NBRC 107235T = BCC 38191T), respectively.