To　improve　the　forming　efficiency　and　quality　of　laser　cladding　formed　unequal　width　parts,　some　corresponding　experiments　were　designed.　A　variable　laser　spot　method　was　put　forward　to　fabricate　single-track　cladding　layers　with　unequal　width　by　inside-laser　powder　feeding　process.　The　influencing　rules　of　continuously　and　piece-wise　changed　laser　defocusing　distances　on　the　forming　quality　of　thin-walled　parts　were　analyzed　during　the　process　of　changing　laser　spots.　The　experimental　results　showed　that　there　was　a　“self-healing”　effect　on　the　cladding　layer　morphology　with　laser　defocusing　distance　from　-3　mm　to　-5　mm　and　the　surface　forming　quality　of　cladding　layers　was　good,　and　that　the　forming　quality　was　poor　with　the　laser　defocusing　distance　from　0　mm　to　-2　mm.　The　height　of　cladding　layer　firstly　increased　then　decreased　with　the　growth　of　laser　defocusing　distance　in　negative　laser　defocusing　range,　and　there　was　a　maximum　value　at　-2.5　mm.　Within　the　range　of　positive　laser　defocusing,　the　cladding　layer　height　had　the　same　changing　trend　as　in　negative　laser　defocusing　range　with　the　laser　defocusing　distance,　and　also　had　a　peak　value　at　2.5　mm.　To　obtain　continuous　sizes　of　the　cladding　layers,　a　splicing　method　of　“self-healing　interval”　was　put　forward　for　variable　laser　defocusing　distances.　Hence,　the　thin-walled　parts　were　fabricated　layer　by　layer　with　continuously　changed　width　from　1　mm　to　3　mm.　This　study　may　provide　a　guidance　for　the　fabrication　of　thin-walled　parts　with　variable　width　by　laser　cladding　forming　using　inside-laser　powder.　©　2016,　Editorial　Office　of　Journal　of　Xi＇an　Jiaotong　University.　All　right　reserved.