Anthocyanins, also called anthocyans, are a group of plant secondary metabolites of flavonoid derivatives. Anthocyanins play an important role in mediating plant stress responses. However, whether anthocyanins are also involved in regulating phyllosphere bacterial communities remains unknown. To evaluate the differences of phyllosphere bacterial communities in plants with different anthocyanin contents, this study analyzed the phyllosphere bacterial communities of two cultivars of elephant grass with contrasting anthocyanins content, Pennisetum purpureum cv. Purple (Purple) with a high amount of anthocyanins and P. purpureum cv. Mott (Mott) with relatively low anthocyanins. The anthocyanins content determination results showed that the anthocyanins content in Purple leaves was nearly 20 times of that in Mott leaves. High throughput sequencing of 16S rRNA and analysis of the microbiome community indicated that though alpha diversity was not significantly changed, the bacterial communities of Purple was significantly different from that of Mott. In Purple, the relative abundance of endopphytic Proteobacteria and Bacteroidetes, and epiphytic Deinococus-Thermus were significantly increased, whereas epiphytic Bacteroidetes and Firmicutes were significantly decreased. The composition of microbiomes (ANCOM) at the OTU level, the relative abundance analysis at the genus level and correlation analysis between epiphytes and anthocyanins showed that the relative abundance of Methylobacterium, Unclassified Methylobacteriaceae and Deinococcus, which showed a significant positive correlation with anthocyanins content, were significantly increased in the episphere of Purple. In summary, the phyllosphere bacterial communities were significantly different between Purple and Mott. The findings from this work would provide new insights into the understanding of the superior forage value of P. purpureum cv. Purple, and lay a foundation to further investigate the mechanism of how plant secondary metabolism products regulate phylloshpere microorganisms.