Abstract：Mir-34 is a family of microRNAs that is highly conserved in evolution and is involved in many important life activities. In this study, the sequences characteristics between spa-miR-34 of Scylla paramamosain from the database constructed by our laboratory and miR-34 of other animals from the miRBase were compared, and then the spa-miR-34 target genes were predicted by two online tools: RNAhybrid and Segal Lab. The functional annotation and signal pathway enrichment of these target genes were analyzed using blast2go software. The results showed that the number of the predicted pa-miR-34 target gene was 66, and the functions of these genes are mainly distributed in the biological processes of oxidation-reduction, phosphorylation, calcium ion transmembrane transport, transcription, etc. Signal pathways related to these genes are mainly concentrated in the metabolism of arginine and proline metabolism, antibiotic biosynthesis, phenylpropion biosynthesis, glycolysis and glycogenation, and other synthetic metabolic pathways. The predicted gene family and pathways of the spa-miR-34 target genes also include CHH family, ERK pathway, cell cycle and UPP pathway, and SUMO pathway. In addition, ecdysteroid receptor gene was also one of the predicted target genes. It is speculated that spa-miR-34 plays an important role in the reproduction, molt and the metabolism of amino acids and other substances. This study provides an important reference for further understand the role of spa-miR-34 in S. paramamosain.