Abstract: Objective To observe the correlation between in vivo inflammation severity and insulin resistance in obstructive sleep apnea syndrome （OSAS） patients with hypertension. Methods Of the 70 severe OSAS patients diagnosed with PSG, 40 were found to be complicated by hypertension. Serum FINS, peptide C and CRP levels were measured using a fully automatic biochemical device. Homeostasis model assessment was used to calculate the insulin resistance （IR） index and the function index of islet β cells. Results The serum levels of true insulin, peptide C, CRP, IR index, function index of islet β cells were higher in OSAS patients with hypertension than in those without hypertension. Conclusion Chronic inflammation may play a role in the development of hypertension in OSAS patients due to formation of insulin resistance.