This study aimed to investigate the clinical and laboratory as well as radiological features of spondyloarthritis (SpA) patients with thrombocytosis and to explore risk factor for thrombocytosis in SpA patients and to assess the effect of antitumor necrosis factor-α (anti-TNF-α) therapy on platelet count in SpA patients with thrombocytosis. The gene discussed is TNF; the disease is spondyloarthropathy.