Although many different types of G-protein coupled receptors (GPCRs) are functionally expressed in neutrophils, no reports have demonstrated functional expression of umami taste receptor in these cells. In this study, we observed that mouse neutrophils express the umami taste receptor heterodimeric T1R1/T1R3 through quantitative RT-PCR analysis. We also found that stimulation of mouse neutrophils with L-alanine or L-serine, which is a ligand for the umami taste receptor, elicited not only ERK or p38 MAPK phosphorylation but also neutrophil chemotactic migration. Moreover, addition of L-alanine or L-serine markedly blocked the production of several cytokines including TNF-α, CCL2, and IL-10 induced by lipopolysaccharide through inhibition of NF-κB activity or STAT3 phosphorylation in neutrophils. Our findings demonstrate that neutrophils express the umami taste receptor, and tastants stimulate neutrophils, resulting in chemotactic migration, and attenuation of LPS-induced inflammatory response.