Recently,　ammonia　is　considered　to　be　an　energy　medium　for　hydrogen　or　energy　storage　and　ammonia/hydrogen　can　be　a　potential　fuel　blend　for　the　spark-ignition　engine.　Nevertheless,　the　combustion　properties　of　ammonia/hydrogen　mixtures　could　be　distinctive　under　different　initial　conditions.　In　this　study,　several　essential　combustion　properties,　including　laminar　burning　velocity,　minimum　ignition　energy,　NOx　and　ammonia　emissions,　combustion　efficiency,　and　mixture　heating　values　of　ammonia/hydrogen/air　premixed　combustion　were　extensively　studied　under　a　wide　range　of　equivalence　ratios　(phi),　hydrogen　fractions　(alpha)　and　different　compression　ratio　using　one-dimensional　laminar　planar　flame　and　compared　with　stoichiometric　methane,　methanol,　and　ethanol　combustion.　The　behavior　of　NOx　generation　changing　with　phi　and　alpha　was　analyzed　in　detail.　Results　showed　that　most　properties　of　ammonia/hydrogen　combustion　could　be　comparable　to　that　of　hydrocarbon　fuels　under　engine-relevant　conditions,　except　for　the　mixture　heating　value　is　slightly　lower　in　all　conditions.　Besides,　the　NO　mole　fraction　non-monotonically　changes　with　phi　and　alpha　due　to　the　competition　between　the　effects　caused　by　the　reduction　of　nitrogen-atom　species　and　the　enrichment　of　H/O　radicals.　The　NO　mole　fraction　of　stoichiometric　ammonia/hydrogen　could　be　even　lower　than　that　of　hydrocarbons.　Considering　the　properties　of　hydrocarbon　fuels　as　a　reference,　promising　working　conditions　for　ammonia/hydrogen　mixtures　are　phi　from　1.0　to　1.05　and　alpha　from　40%　to　60%.　Besides,　a　high　compression　ratio　is　more　suitable　for　ammonia/hydrogen　mixtures　due　to　the　excellent　knock　resistance　ability　of　NH3/H-2　and　better　improvement　than　hydrocarbon　fuels　under　high　compression　ratio.　(C)　2020　Hydrogen　Energy　Publications　LLC.　Published　by　Elsevier　Ltd.　All　rights　reserved.