Many researches show that miRNAs are involved in many vital biological processes, including cell development, cancer progression, and immune system, by binding to the 3untranslated regions of their target genes.This leads to translational repression of the target gene or stimulate rapid degradation of the target transcript.Therefore, the function similarity of miRNAs can be measured by the similarity between their target genes.Further, miRNAs usually accomplish a specific function in the form of group.