The populations of Myxococcus, a gram-negative bacteria, is accumulated in the rhizospheric soil of allelopathic rice PI312777 and significantly larger than that of non-allelopathic rice Lemont, which suggests that Myxococcus plays a potential role in the rhizospheric biological process of PI312777 in suppression of weeds. In this study, the Myxococcus xanthus separated from the rhizospheric soil of PI312777 was used to study the interaction with ferulic acid (FA). The results show that exogenous FA promotes the cell proliferation of M. xanthus. A dimethyl labeling quantitative proteomic technique was used to reveal the protein expression on M. xanthus induced by FA. A total of 76 proteins were found up-regulated whilst 56 proteins were down-regulated in the FA-induced M. xanthus. These up-regulated proteins were involved in the cell growth, motility, signal response and transduction, metabolic process, biosynthesis of secondary metabolites, and social predation. Some target proteins, including frzS, BolA/YrbA family protein, methyl accepting chemotaxis protein, ABC transporter, and ATP-binding protein were selected to detect their genes transcript level, which showed that transcript level of the five genes was also up-regulated in the 0.10 mM FA-induced M. xanthus compared to the FA absent control. Additionally, transcript level of five other gene members from frz multigene family including frzA, frzB, frzCD, frzE, and frzG were also significantly up-regulated. Jointed application of FA and M. xanthus led to strongest growth inhibition of barnyardgrass. The results indicated that FA induced the chemotaxis and cell proliferation of M. xanthus, whilst the interactions between FA and M. xanthus lead to enhance growth inhibition on barnyardgrass.