Hydrogen　and　ammonia,　as　two　renewable　carbon-free　combustibles,　are　considered　to　be　potentially　excellent　alternative　fuels　for　internal　combustion　engines.　Since　hydrogen　and　ammonia　have　opposite　and　complementary　combustion　characteristics,　the　co-combustion　of　ammonia　with　hydrogen　is　reasonable.　However,　there　are　few　detailed　experimental　studies　of　load　control　strategies　for　an　ammonia‑hydrogen　engine.　In　this　study,　four　load　control　strategies　including　the　variation　of　ammonia　volume　share　(AVS),　qualitative　control,　quantitative　control,　and　adjustment　of　intake　variable　valve　timing　(VVT)　are　proposed　and　assessed　for　their　applicability　in　an　ammonia/hydrogen　dual-fuel　engine.　The　ignition　and　combustion　characteristics　of　ammonia　do　not　allow　for　high　thermal　efficiency,　so　the　Miller　cycle　is　introduced　to　improve　engine　performance.　The　engine　employs　fuel　supply　modes　of　ammonia　port　injection　and　hydrogen　direct　injection　at　1500　rpm.　In　general,　the　engine　achieves　higher　brake　mean　effective　pressure　(BMEP)　and　brake　thermal　efficiency　(BTE)　at　different　AVS.　Moreover,　qualitative　control　and　adjustment　of　intake　VVT　allow　the　engine　to　own　a　wide　regulation　range　of　BMEP　and　maintain　the　BTE　of　more　than　37%　under　most　conditions.　However,　quantitative　control　appears　to　be　an　inadequate　strategy　for　the　engine　due　to　the　lower　BMEP　and　BTE.　©　2023