In　this　paper,　we　study　the　effect　of　B　introduction　in　various　Heusler　alloys　on　their　structural　and　magnetic　properties.　Samples　with　nominal　stoichiometry　Fe50+xCu25-xGa25,　Fe50+xCu25-xAl25,　and　Fe50+xCo25-xGa25(x　=　0-10)　with　the　addition　of　excess　B　up　to　12　at%　were　prepared　with　Ar　arc-melting　as　base　materials.　The　starting　materials　were　subsequently　converted　to　ribbons　using　melt-spinning　technique　with　velocity　of　35　and　40　m/　s,　while　the　other　parameters　were　kept　fixed.　Basic　study　of　the　alloys　was　conducted　with　various　characterization　techniques　(energy　dispersive　X-ray　spectrometry,　X-ray　powder　diffraction,　and　magnetization　versus　temperature　and　field).　The　materials　were　thermally　treated　at　various　temperatures　between　873　and　1073　K　and　the　effect　on　the　structure　and　magnetic　properties　was　studied.