Diet　is　a　crucial　factor　that　shapes　the　composition　of　the　microbiota　throughout　the　life　cycle.　Systemic　chronic　inflammation　and　microbial　imbalance　may　play　a　key　role　in　the　pathogenesis　of　cognitive　disorders.　Inflammatory　diets　can　influence　the　host　microbiome　and　inflammatory　state.　This　study　investigated　the　impact　of　the　inflammatory　potential　of　the　diet　on　the　diversity　and　composition　of　the　oral-gut　microbiome,　as　well　as　on　cognitive　performance,　in　older　adults　over　60　years　of　age.　The　Energy-adjusted　Dietary　Inflammatory　Index　(E-DII)　and　16S　rRNA　sequencing　were　used　to　analyze　dietary　inflammatory　properties　and　oral-gut　microorganisms　in　54　patients.　The　results　showed　that　significant　differences　in　the　diversity　of　oral　microbiota　among　different　E-DII　groups　was　detected　(p　＜　0.05),　whereas　gut　microbiota　diversity　didn＇t　exhibit　variations.　In　the　anti-inflammatory　diet　group,　the　class　Saccharimonadia,　the　order　Corynebacteriaceae,　the　genera　TM7x,　Eubacterium_yurii_group,　and　Centipeda　were　more　abundant　in　oral　microbiomes,　and　lower　abundance　of　Holdemanella　and　Haemophilus　was　observed　in　the　gut　microbiomes.　Specific　oral　and　gut　genera　were　associated　with　MMSE,　MoCA,　AVLT-LR,　BNT,　and　VFT　scores　(p　＜　0.05).　These　results　provide　insights　into　anti-inflammatory　diets　were　associated　with　an　increased　abundance　of　beneficial　microbes,　and　a　specific　oral　and　gut　microbial　composition　was　associated　with　cognition.