Electron　beam　powder　bed　fusion　(EB-PBF)　is　a　key　metal　additive　manufacturing　(AM)　technology　known　for　its　high　energy　absorption　and　low　heat　stress.　However,　the　high　surface　roughness　of　EB-PBF　parts　has　limited　its　broader　application.　To　address　this　issue,　this　paper　proposes　a　dashed-scan　contouring　strategy　to　obtain　lower　surface　roughness　in　EB-PBF.　This　strategy　involves　melting　the　contour　in　the　form　of　segmented　staggered　scans　and　employing　high-frequency　jumping　of　the　electron　beam　(EB)　to　melt　multiple　positions　synchronously.　A　comprehensive　analysis,　combining　experimental　investigations　and　multi-physical　simulations,　elucidates　the　intrinsic　connection　between　control　processes　and　melt　pool　stability.　Results　show　that　by　controlling　the　length-to-width　ratio　of　the　melt　pool,　regulating　overlap　distances　between　melt　pools,　and　fine-tuning　cooling　times,　balling　phenomena　and　Plateau-Rayleigh　instabilities　can　be　suppressed.　Additionally,　these　measures　effectively　mitigate　irregularities　in　track　formation　when　compared　to　the　traditional　process.　Experimental　validation　demonstrates　the　efficacy　of　the　approach,　achieving　reduced　surface　roughness　(Ra)　of　thin-walled　Ti6Al-4　V　parts　from　over　25　mu　m　to　below　12.6　mu　m,　while　enhancing　dimensional　accuracy　and　reducing　melt　anomalies　at　corners.　The　proposed　dashed-scan　contouring　strategy　opens　new　avenues　for　AM　of　highly　reliable　and　intricate　structures,　such　as　lattice　sandwich　structures,　thin　walls,　and　internal　flow　passages.