Based　on　spectral　beam　combining　technology,　with　diffraction　grating　and　external　cavity　feedback,　each　element　of　an　array　of　diode　laser　is　locked　at　different　wavelengths　in　a　narrow　linewidth　by　inserting　a　beam　shaping　system.　And　the　output　beam　is　an　approximately　parallel　light　along　the　direction　of　combination.　Beam　quality　improvement　and　linewidth　narrowing　of　an　array　of　diode　laser　are　achieved.　The　standard　diode　laser　array　used　in　our　experiment　has　19　elements,　with　a　width　of　100　μm　and　a　period　of　500　μm　for　each　element.　Experiment　is　conducted　on　different　spectral　beam　combing　setups,　including　spectral　beam　combing　after　collimation　in　both　fast　and　slow　axes,　spectral　beam　combing　after　beam　shaping　and　beam　combing　in　an　external　cavity　with　narrow-line　width.　The　combining　output　beam　has　the　same　beam　quality　as　that　of　a　single　emitter　and　the　linewidth　of　such　a　beam　is　narrow.　The　experiment　results　are　analyzed.