This randomized, double-blind, placebo-controlled trial evaluated the uric acid (UA)-lowering effect of Limosilactobacillus reuteri CCFM1132 in young males with hyperuricemia. Participants received 1 × 1010 CFU of L. reuteri CCFM1132 (n = 34) or placebo (n = 31) daily for 8 weeks. After the intervention, serum UA concentration significantly decreased, along with a reduction in xanthine oxidase (XOD) activity compared to the placebo group (P < 0.01). Indicators of liver (aspartate transaminase and alanine transaminase) and renal (urea and creatinine) functions improved. Short-chain fatty acid (SCFA) concentrations significantly increased, with an upregulated abundance of SCFA producers (Fusicatenibacter, Ruminococcaceae UCG_014, and Ruminococcus 1) in the gut. Additionally, correlation analysis revealed that concentrations of SCFAs, particularly acetate and butyrate, were strongly negatively correlated with UA concentration and XOD activity. These findings suggest that L. reuteri CCFM1132 relieves hyperuricemia by enhancing the abundance of SCFA producers in the gut to promote SCFA production and by suppressing XOD activity. This study provides a valuable reference for developing new treatments for hyperuricemia.