Gene Regulatory Networks (GRNs) model some of the mechanisms that regulate gene expression. Among the computational approaches available to model and study GNRs, Boolean Network (BN) emerged as very success- ful to better understand both the structural and dynamical properties of GRNs. Nevertheless, the most widely used models based on BNs do not include any post-transcriptional regulation mechanism. Since miRNAs have been proved to play an important regulatory role, in this paper we show how the post-transcriptional regulation mechanism mediated by miRNAs has been included in an enhanced BN-based model. We resort to the miR-7 in two Drosophila cell fate determination networks to verify the effectiveness of miRNAs modeling in BNs, by implementing it in our tool for the analysis of Boolean Network