The　mix　design　of　the　stone　matrix　asphalt　(SMA)　mixture　is　critical　to　its　performance　and　thereby　has　attracted　considerable　attention.　In　this　research,　abiding　by　the　principals　of　orthogonal　experimental　design,　a　series　of　laboratory　tests　are　conducted　to　assess　and　optimise　the　SMA-13　mixture　mix　designs.　Different　levels　of　three　critical　factors,　gradation,　asphalt-aggregate　ratio,　and　fibre　contents,　are　applied　in　the　factorial　experimental　designs.　Five　performance　measures,　residual　stability,　dynamic　stability,　fatigue　lifespan,　bending　strength,　and　coefficient　of　friction,　are　tested.　With　the　laboratory　testing　results,　weight-matrix　analysis　is　employed　to　identify　the　impact　of　different　levels　of　different　factors　on　overall　performance.　Based　on　the　results,　the　influences　of　the　three　factors　are　ranked:　gradation,　asphalt-aggregate　ratio,　and　fibre　contents,　from　the　most　influential　to　the　least.　Furthermore,　analyses　are　conducted　to　determine　the　optimum　SMA-13　mix　design　for　four　representative　climate　zones　in　China.　Results　are　verified　with　the　compared　mixture　groups.