Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)　(PEDOT:PSS)　is　a　widely　used　anode　interlayer　(AIL)　in　organic　solar　cells　(OSCs).　However,　the　intrinsic　acidity　and　hygroscopic　nature　of　PSS　ions　in　PEDOT:PSS　have　been　proven　to　cause　electrode　corrosion　and　deteriorate　device　performance.　Herein,　a　straightforward　method　is　reported　to　enhance　the　water　resistance　of　PEDOT:PSS　by　incorporating　tris[bis(methoxymethyl)amino]-1,3,5-triazine　(HM)　as　a　cross-linker.　The　cross-linking　reaction　between　PSS　and　HM　neutralizes　the　acidity　of　PEDOT:PSS　and　forms　a　stable,　hydrophobic　network.　Additionally,　the　aggregation　morphology　of　PEDOT:PSS　was　regulated　by　HM,　improving　the　conductivity　and　work　function,　thereby　resulting　in　enhanced　hole　extraction　and　transport　ability.　Devices　incorporating　PEDOT:PSS-HM　demonstrated　improved　power　conversion　efficiency　(PCE)　of　19.03%　compared　to　17.88%　for　those　using　standard　PEDOT:PSS.　The　neutral　pH　and　water-resistant　nature　of　PEDOT:PSS-HM　effectively　improved　the　long-term　stability　of　OSCs　with　a　T80　of　over　400　h　under　continuous　illumination.　Moreover,　after　aging　the　PEDOT:　PSS-HM　film　for　216　h　at　80%　relative　humidity　and　40　°C,　it　can　be　still　used　as　AIL　to　fabricate　efficient　OSC　devices.　This　work　presents　a　simple　and　effective　approach　to　preparing　a　non-corrosive　and　stable　PEDOT　derivative,　offering　valuable　insights　for　the　development　of　high-performance　AIL　materials.　©　Science　China　Press　2025.