Abstract: Alternative splicing is a key process of gene expression regulation. The histone modifications are closely correlated with alternative splicing, however, its regulatory mechanisms remain unclear. In order to reveal the relationships between histone modifications and alternative splicing, by analyzing the RNA-Seq data, the exon skipping events from human embryonic lung fibroblast cell line were obtained. Subsequently, the relationships among different kinds of histone modifications were analyzed for both excluded and included exons in exon skipping event. Finally, the Bayesian network was built to deduce the casual relationships among histone modifications in exon skipping event.