Abstract: In order to understand the character of LemiR828 in tomato（Lycopersicum esculentum）LA1996（with anthocyanin fruit，Aft），the precursor sequence and potential target gene of LemiR828 were obtained by PCR using cDNA as template. The expression of LemiR828 and its target gene in tomato fruits were also evaluated by real-time quantitative PCR. LemiR828-guided cleavage and the target site identified on putative Trans-Acting SiRNA Gene 4（LeTAS4）mRNA were validated using RLM 5′RACE. The precursor sequence of LemiR828 was shown to contain a complete hairpin structure. Moreover，the expression of LemiR828 and its target gene LeTAS4 in tomato fruits differed in developmental stages. During green fruit stages，the transcriptional level of LemiR828 and LeTAS4 was low and did not seem to be related to negative regulation；however，in mature fruit stages，their expression was high，and LemiR828 negatively regulated the expression of LeTAS4. The mature LemiR828 targeted a sequence of high complementarity in LeTAS4 mRNA and sheared the 10th position in LeTAS4 mRNA from LemiR828 5? end.Thus，during specific developmental stages in Aft tomato fruits，LemiR828 and LeTAS4 were involved in the regulation of fruit development and the expression of LeTAS4 was negatively regulated by LemiR828，probably regulated anthocyanin synthesis at particular stages.

Key words: tomato, LemiR828, LeTAS4, anthocyanin biosynthesis