Selective　laser　melting　at　various　laser　inclination　angles　was　used　to　prepare　Hastelloy　X　alloy　specimens.　The　morphology,　fracture,　tensile　strength,　stress,　and　strain　of　Hastelloy　X　alloy　specimens　were　studied　using　optical　microscopy,　scanning　electron　microscopy,　and　a　tensile　tester.　The　temperature　field　of　the　manufacturing　process　was　analyzed　based　on　finite　element　analysis,　and　the　internal　relationship　between　the　temperature　field　and　the　process　was　constructed　in　terms　of　cooling　speed.　The　results　show　that　the　temperature　field　is　a　dynamic　process　with　a　high　cooling　rate;　the　average　cooling　rate　reaches　3.23　x　10(6)　degrees　C　x　s(-1).　The　greater　the　inclination　angle,　the　greater　the　thermal　gradient,　resulting　in　higher　cooling　rates.　Due　to　the　cross-influence　of　grain　refinement　at　high　cooling　rates　and　residual　stress,　the　tensile　strength　and　yield　strength　of　Hastelloy　X　alloy　showed　first　increasing　and　then　decreasing　trends　with　respect　to　inclination　angle.　However,　at　an　inclination　angle　of　30　degrees,　the　voids　and　crack　defects　of　Hastelloy　X　alloy　fractures　were　reduced,　and　the　tensile　strength　and　yield　strength　reached　881.38　and　701.60　MPa,　respectively.　At　this　angle,　the　mechanical　properties　were　excellent　and　met　the　requirements　of　the　aviation　industry.