In order to screen Lactobacillus plantarum with assistant uric acid-lowering function, five species of L. plantarum independently isolated and identified by us were evaluated its ability to degrade purine nucleosides in vitro. L. plantarum UA419, a strain with strong degradation ability of purine nucleoside, was further studied. The L. plantarum UA419 was given to the hyperuricemia rats (induced by potassium oxonate combined with fructose) by gavage for continuous 2 weeks. The uric acid, xanthine oxidase and inflammatory factor levels in serum were measured and western bolt was used to explore the mechanism of the strain’s lowering uric acid. The results showed that L. plantarum UA419 could significantly reduce serum indexes, including uric acid (39.71%), xanthine oxidase (15.36%), leukotrienes (25.81%), thromboxane (38.40%) and inflammatory factor levels (IL-1 26.89%, IL-8 10.40%, IL-6 17.29%, IL-1β 20.95% and TNF-α 23.09%). L. plantarum UA419 might be a promising agent for gouty treatment to inhibit renal NF-κB/NLRP3 inflammasome activation via the AMPK/SIRT1 pathway. These results indicated that L. plantarum UA419 plays an assistant uric acid-lowering effect.