Abstract: 【 Objective】MicroRNA156s(miR156s)is a kind of very conservative small RNA family. The study on its participation in the regulatory network of gene expression during seed maturation in plants will play a key role in the improvement of seed qualities and yields.【Methods】Based on the reporter gene screening system established by predecessors, the GUS activities of mutants MIM156-gus and SPLs-ox were analyzed. The tissue expression characteristics of different members in miR156 family and expression of key regulatory factors during mutant seed maturation process were identified by qRT-PCR technology.【Results】After GUS staining, the four mutants showed GUS phenotype in 14-day-old seedlings, which were MIM156 and its target genes SPL2, SPL10 and SPL11 with gus23 as background material. In the miR156 family, the expression level of miR156a, d, e and j in silique was at least 20 times that of in 14-day-old seedlings. The expression levels of LEC1, ABI3 and FUS3 in the MIM156 down-regulated mutants were significantly increased to different degrees.【Conclusion】The down-regulation of miR156 and the over-expression of SPLs induced the ectopic expression of SSPs genes. Moreover, MIM156 promoted the expression of LEC1, ABI3 and FUS3 genes. These indicated that miR156/SPLs, as a regulatory factor, was involved in the process of plant seed maturation.