In　this　research,　nanosized　Ag　reinforcement　particles　were　incorporated　by　mechanical　means　into　a　promising　lead-free　solder,　Sn-0.7Cu,　in　an　effort　to　improve　the　comprehensive　property　of　the　Sn-0.7Cu　solder.　Wettability,　mechanical　performance,　and　creep-rupture　life　tests　were　conducted　to　study　the　difference　between　Sn-0.7Cu　solder　and　its　composite　solder　with　different　Ag　reinforcement　volume　fractions.　Experimental　results　indicated　that　the　composite　solders　and　their　joints　showed　better　wettability　and　mechanical　properties,　as　well　as　longer　creep-rupture　lives,　than　Sn-0.7Cu　solder.　The　composite　solder　with　1vol.%Ag　reinforcement　addition　exhibited　the　best　comprehensive　property　as　compared　to　the　composite　solders　with　other　reinforcement　volume　fractions.　Systematic　creep-rupture　life　tests　were　conducted　on　the　1vol.%Ag-reinforced　Sn-0.7Cu-based　composite　solder　joints.　Significant　enhancement　of　the　creep-rupture　lives　were　found　in　the　composite　solder　joints　under　different　stress　and　temperature　combinations　as　compared　to　the　Sn-0.7Cu　solder　joint.　Ductile　rupture　surfaces　were　exhibited　in　most　of　the　broken　solder　joints.