We determined the precise sequence of peach miR167a by using miRRACE PCR reactions of the peach (Prunus persica) cultivar ‘Xiaobaifeng’, cloned three predicted target genes PpARF6, PpARF8 and PpARF6like of ppemiR167a and analyzed the phylogenetic and conserved domains of the three genes. The target genes of ppemiR167a were further identified by degradome sequencing technology, and the mode and frequency of interaction between ppemiR167a and the target genes were analyzed. The results showed: (1) the accurate sequence of ppemiR167a was different from the predicted sequence in the 1 nucleotide at the 5′ end and 3′ end. All the three target genes ARFs contained highly conserved B3 and auxin response DNA binding domains. Phylogenetic tree analysis indicated that PpARF6, PpARF8 and PpARF6like in peach were closely related to Apricot, followed by plum and sweet cherry. (2) The results of the degradome sequencing displayed that only PpARF8 could be cleavaged by ppemiR167a among the three predicted target gene and no cleavage sites were detected on PpARF6 and PpARF6like. (3) The analysis of gene expression of exogenous IAA treated peach showed that the expression of miR167a after treatment was lower than that in the CK, while the expression of its target gene PpARF8 and the 3′end cleavage production were higher than those in the CK. Taken together, these findings showed that ppemiR167a in peach fruit involved in auxin signaling pathway and participated in the regulation of fruit development by mediating the cleavage of its target gene PpARF8.