Serine　proteases,　a　significant　class　of　enzymes　comprising　approximately　one-third　of　known　human　proteases,　are　ubiquitously　present　across　various　organisms.　These　enzymes　typically　exhibit　highly　conserved　catalytic　domain　structures,　and　their　activity　is　stringently　regulated　within　the　body,　playing　a　pivotal　role　in　numerous　physiological　processes.　Dysregulation　of　serine　protease　activity　can　result　in　severe　consequences,　including　excessive　inflammation,　heightened　risk　of　thrombosis　and　cancer,　and　even　mortality.　Serine　protease　inhibitors　have　emerged　as　critical　regulators,　offering　a　broad　range　of　physiological　functions　such　as　maintaining　the　coagulation-fibrinolysis　balance,　modulating　inflammatory　responses,　accelerating　wound　healing,　promoting　apoptosis,　and　providing　antitumor　and　antiviral　effects.　As　a　result,　the　development　of　serine　protease　inhibitors　has　become　increasingly　vital.　In　recent　years,　significant　progress　in　the　study　of　serine　proteases　has　led　to　the　pivotal　role　of　various　serine　protease　inhibitors　in　clinical　diagnosis　and　treatment.　This　review　explores　the　fundamental　mechanisms　of　serine　protease　inhibitors,　summarizes　those　that　have　been　successfully　integrated　into　clinical　practice,　and　discusses　the　challenges　encountered　in　their　development　along　with　partial　solutions.　These　advancements　lay　the　groundwork　for　further　refinement　and　innovation　in　serine　protease　inhibitor　therapeutics.