High-beam　quality　and　kilowatt-　class　diode　laser　system　was　reported　in　the　paper　using　four　wavelengths　for　the　wavelength　multiplexing　and　polarization　multiplexing.　Through　the　beam　shaping　method,　the　beam　quality　less　than　12mm·mrad　was　got　in　both　the　fast　axis　and　the　slow　axis,　so　the　laser　beam　could　be　coupled　into　200μm　fiber.　The　optical　efficiency　of　the　beam　shaping　device　was　more　than　94　%.　The　overall　opt-opt　conversion　efficiency　of　the　laser　system　reached　85.9　%.　The　overall　electro　optical　conversion　efficiency　was　45　%.　The　power　density　was　over　107　W/cm2.The　output　power　density　and　the　beam　quality　of　the　laser　system　can　meet　the　laser　welding　system,　marking　system,　cutting　system　and　other　industrial　processing　needs.