Hydrogen　is　very　promising　as　engine　fuel　due　to　its　excellent　combustion　and　emission　characteristics.　In　order　to　improve　the　emission　of　a　spark-ignited　gasoline　engine　car　a　set　of　hydrogen　injection　system　was　added　to　its　gasoline　engine　and　the　engine　can　be　fuelled　with　gasoline,　hydrogen　or　both.　An　electronic　control　system　was　developed　and　applied　to　control　the　injection　timings　and　duration　of　hydrogen　and　gasoline.　The　basic　composition　of　the　control　system　and　the　fuel　injection　control　strategy　of　the　hybrid　hydrogen-gasoline　engine　were　studied　in　this　paper.　Finally　the　tailpipe　emission　of　the　hybrid　hydrogen-gasoline　powered　car　was　tested　over　the　NEDC　driving　cycle,　and　compared　with　that　of　the　original　gasoline　car.　The　experimental　results　showed　that　the　emission　of　the　hybrid　hydrogen-gasoline　powered　car　is　improved　and　can　meet　China-IV　emission　standard.