In　order　to　achieve　climate　goals　as　soon　as　possible,　it　is　necessary　to　reshape　the　energy　mix　to　replace　fossil　energy　with　carbon–neutral　fuels　as　soon　as　possible.　Ammonia　is　a　good　medium　for　energy　storage,　has　a　large　industrial　scale　and　a　well-developed　infrastructure.　To　address　the　problems　of　NOx　emission　and　low　exhaust　energy　of　ammonia-hydrogen　engines,　this　study　proposes　a　rich　burn　strategy.　Firstly,　a　commercial　spark　ignition　(SI)　internal　combustion　engine　(ICE)　was　modified　to　achieve　a　dual　fuel　supply　of　ammonia　and　hydrogen.　The　engine　was　run　at　a　steady　state　of　1500　rpm　with　the　intake　manifold　absolute　pressure　(MAP)　maintained　at　60　kPa,　and　the　ammonia　and　hydrogen　supplies　were　adjusted　to　achieve　different　mixing　ratios　and　excess　air　ratios.　The　experimental　results　showed　that　the　rich　burn　strategy　could　significantly　reduce　the　NOx　emission　and　increase　the　exhaust　temperature　of　the　ammonia-hydrogen　engine　when　the　excess　air　coefficient　was　below　0.8.　The　rich　burn　strategy　can　appropriately　increase　the　engine　power　output,　but　it　has　some　influence　on　the　brake　thermal　efficiency　(BTE).　©　2023　Elsevier　Ltd