The　rotary　engines　may　encounter　high　fuel　consumption　and　emissions　due　to　its　narrow　and　long　combustion　chamber　design.　The　low　ignition　energy　and　high　flame　speed　of　hydrogen　may　help　improve　the　combustion　of　rotary　engines.　In　this　paper,　a　gasoline　rotary　engine　equipped　with　gasoline　and　hydrogen　injectors　was　developed　to　investigate　the　combustion　and　emissions　of　hydrogen-blended　gasoline　rotary　engines.　The　engine　was　run　at　3000　rpm　and　a　manifolds　absolute　pressure　of　37.5　kPa　with　the　stoichiometric　excess　air　ratio.　The　spark　timing　was　set　to　be　25　CA　before　the　top　dead　center.　The　engine　was　first　fueled　with　the　pure　gasoline　and　then　blended　with　the　hydrogen.　The　hydrogen　volume　fractions　in　the　intake　were　gradually　increased　from　0%　to　5.2%.　The　results　showed　that　the　combustion　pressure,　brake　mean　effective　pressure,　cylinder　temperature　and　thermal　efficiency　were　simultaneously　increased　after　the　hydrogen　blending.　The　crank　angle　of　peak　pressure　was　advanced　with　the　hydrogen　addition.　The　hydrogen　enrichment　was　effective　on　reducing　flame　development　and　propagation　periods.　HC　emissions　were　reduced　by　44.8%　when　the　hydrogen　volume　fraction　in　the　intake　was　raised　from　0%　to　5.2%,　CO　and　CO2　emissions　were　also　reduced　after　the　hydrogen　blending.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.