This study investigated the effects of noni fruit flavonoids (NFF) on antioxidant status and anti-inflammatory responses in cashmere goats and explored the underlying mechanisms based on liver transcriptomics and metabolomics. Sixteen male Albas cashmere goats were randomly assigned to two groups: a control (CON) group and a group supplemented with 0.1% NFF. The adaptation and trial periods were 2 and 12 weeks, respectively. The results showed that NFF significantly enhanced antioxidant capacity, with mean increases of 32.9%, 20.7%, and 35.5% for total antioxidant capacity (T-AOC), glutathione peroxidase (GPx), and catalase (CAT) activities, respectively, across serum, liver, spleen, and thymus (p < 0.05). NFF also modulated the inflammatory profile, with a mean increase of 18.0% for interleukin (IL)-10 and mean reductions of 18.6%, 19.4%, and 16.7% for IL-1β, IL-2, and tumor necrosis factor (TNF)-α, respectively, across the serum, liver, and thymus (p < 0.05). Integrative transcriptomic and metabolomic analyses suggested that the AMPK signaling pathway, glutathione metabolism, and TGF-β signaling pathway may be critically involved in mediating these effects. GPX3, GPX8, GCLM, NFKB1, and IL1B were identified as key candidate genes, while adenosine-5′-monophosphate (AMP), cysteinylglycine, and pyroglutamic acid were key differential metabolites. Dietary supplementation with 0.1% NFF enhanced the antioxidant levels and anti-inflammatory response in cashmere goats.