In　the　present　work,　a　simple　fatigue　life　prediction　approach　is　proposed　using　fracture　mechanics　for　laser　beam　welded　Al-alloy　joints　under　variable　amplitude　loading.　In　the　proposed　approach,　variable　amplitude　loading　sequence　is　transformed　into　an　equivalent　constant　amplitude　loading　using　the　root　mean　square　model.　The　crack　growth　driving　force　K-*　is　chosen　to　describe　the　fatigue　crack　growth　rate.　The　influences　of　residual　stress　and　its　relaxation　on　fatigue　life　are　taken　into　account　in　the　proposed　approach.　The　fatigue　lives　are　also　predicted　using　the　traditional　approach　based　on　the　S-N　curves　and　the　rainflow　counting　method.　The　predicted　results　show　that　the　proposed　approach　is　better　than　the　traditional　approach.