Abstract: Single shear lap creep specimens with a 1 mm² cross sectional area were developed using Ag particles enhanced 63Sn37Pb based composite solder to invesitigate the influence of stress on creep behavior of the composite solder. The results indicated that the creep resistance of soldered joints of Ag particles enhanced 63Sn37Pb based composite solder is superior to that of soldered joints produced using the conventional 63Sn37Pb solder. Creep rupture lifetimes of the soldered joints of the composite solder decrease with increasing stress and more sensitive to the stress than those of the conventional 63Sn37Pb eutectic solder.