Abstract:TNACs(tobacco NAC genes) is a novel subgroup of NACs unique to Solanaceaea. Now, little information was available about TNACs of tomato(Solanum lycopersicum). In our previous studies, based on the alignment of sequences from tomato, Arabidopsis and rice, we constructed a unrooted phylogenetic tree and found a subgroup included only 26 SlNACs(Solanum lycopersicum NAC). In this study, we characterized 26 SlNACs further. Of all, 10 SlNACs shared the typical characteristics with TNACs. By the real-time quantitative PCR, we analyzed the expression patterns of the tomato TNACs in different organs and under drought, high salinity and low temperature stresses, respectively. Except for one tomato TNAC, two were expressed in all tested organs and seven showed organ-specific expression patterns. Among ten tomato TNACs, eight were detected to respond to one or more stress treatments. Our findings will provide important clues for predicting the functions of tomato TNACs, and understanding the roles of the group NAC specific to Solanaceaea.