This　paper　presents　an　approach　to　determine　the　optimal　stitching　line　and　propagate　deformation　in　irregular　overlap　for　image　stitching.　First,　determine　the　optimal　stitching　line　that　has　the　lowest　cost　of　some　candidate　lines　in　the　irregular　region;　second,　detect　and　match　the　features　in　the　neighborhood　of　the　optimal　stitching　line　and　calculate　deformation　vectors;　finally,　spread　the　deformation　vectors　to　the　whole　of　image　region　by　Poisson　equation　and　constitute　the　image　gradient　field　that　can　reconstruct　seamless　mosaic.　This　method　has　no　limitation　to　the　shape　of　the　overlapping　area　so　can　reduce　the　juncture　of　structure　and　color　in　the　stitching　images.　Compared　with　other　methods　this　method　can　achieve　better　visual　results　both　in　structure　and　color.　©　2012　ACM.