The expressions of tsa-miR172a and tsa-miR398b in roots of Thellungiella halophila (T.salsuginea),which were screened via Solexa sequencing,were studied by stem-loop RT-PCR methodology.The results showed that tsa-miR172a was up-expressing and tsa-miR398b was down-expressing under the treatment of NaCl (300 mmol·L^-1,72 h).With the stem-loop RT-PCR,tsa-miR172a and tsa-miR398b were amplified and the optical densities of electrophores were analyzed specifically.The ratios of NaCl stress to control were 1.8 and 0.55,which were roughly consistent with the results 2.00 and 0.44 obtained by Solexa.Our study established an effective stem-loop RT-PCR system:three primers,namely miRNA stem-loop primer,miRNA forward primer and miRNA universal reverse primer,were designed for each miRNA.The reactions were incubated at 94℃ for 2 min,followed by 23 cycles of 94℃ for 15 s and 55℃ for 45 s.The stem-loop RT-PCR system to identify miRNAs in Thellungiella was discussed.