Diabetic　retinopathy　(DR)　is　characterized　by　progressive　retinal　vascular　damage　that　ultimately　causes　vision　loss.　The　prognostic　nutritional　index　(PNI),　which　integrates　albumin　and　lymphocytes,　serves　as　an　indicator　of　an　individual＇s　inflammatory　response,　nutritional　condition,　and　immune　system　function.　This　research　aimed　to　explore　the　possible　association　between　PNI　and　DR.　This　was　a　cross-sectional　study　utilizing　data　from　the　National　Health　and　Nutrition　Examination　Survey　(NHANES)　between　2001　and　2018.　Weighted　logistic　regression　analyses　were　employed　to　assess　the　relationship　between　PNI　and　DR　prevalence.　A　total　of　4791　adults　aged　20　years　and　older　were　included　in　the　analysis.　Results　indicated　a　statistically　significant　negative　correlation　between　PNI　and　DR　prevalence.　In　the　fully　adjusted　model,　a　one-unit　rise　in　PNI　corresponded　to　a　7%　reduction　in　the　probability　of　DR　prevalence.　Quartile　analysis　consistently　indicated　that　individuals　in　the　highest　PNI　quartile　had　notably　lower　odds　of　DR　prevalence　compared　to　those　in　the　lowest　quartile.　Additionally,　smooth　curve　fitting　suggested　a　nonlinear　relationship　between　PNI　and　DR.　Subgroup　analysis　reinforced　the　strength　of　the　inverse　association　between　PNI　and　DR　(all　p　for　interaction　＞　0.05).　This　nationally　representative　study　demonstrated　a　significant　inverse　relationship　between　PNI　levels　and　DR　prevalence　among　diabetic　adults　in　the　United　States.　Our　findings　emphasize　the　potential　role　of　maintaining　optimal　PNI　values　in　preventing　the　development　of　DR.