In　this　paper,　using　laser　direct　writing　technology,　a　femtosecond　laser　was　used　to　process　a　periodic　grating　structure　on　a　99.99%　tungsten　target.　The　specific　parameters　of　the　laser　are　as　follows:　a　center　wavelength　of　800　nm,　pulse　width　of　35　fs,　repetition　rate　of　1　kHz,　and　maximum　single　pulse　energy　of　3.5　mJ.　The　surface　morphology　of　the　samples　was　characterized　and　analyzed　using　a　scanning　electron　microscope　(SEM,　Coxem,　Republic　of　Korea)　and　atomic　force　microscope　(AFM,　Being　Nano-Instruments,　China).　The　thermal　radiation　infrared　spectrum　of　the　tungsten　target　with　grating　structures　was　measured　using　a　Fourier　transform　infrared　spectrometer　(Vertex　70,　Bruker,　Germany).　The　results　show　that　as　the　laser　fluence　increases,　the　depth　of　the　groove,　the　width　of　the　nanostructure　region,　and　the　width　of　the　direct　writing　etching　region　all　increase.　The　peak　thermal　radiation　enhancement　appears　around　the　wavenumber　of　900　cm-1　when　the　laser　fluence　is　sufficient.　Additionally,　its　intensity　initially　increases　and　then　decreases　as　the　laser　fluence　increases.　If　the　grating　period　is　too　large,　the　impact　on　thermal　radiation　is　not　clear.　The　heating　temperature　significantly　affects　the　intensity　of　thermal　radiation　but　does　not　have　a　noticeable　effect　on　the　position　of　thermal　radiation　peaks.　Moreover,　the　relative　weighting　of　different　wavenumbers　changes　as　the　temperature　increases.