Abstract: Background Obstructive sleep apnea syndrome（OSAS）is a common disease.Prevalence rate of hypertention among patients of OSAS is higher than that without OSAS.Objective To test the hypothesis that in- flammatory factors are involved in the pathogenesis of OSAS with hypertension.Methods Based on aspea index （AHI）,136 subjects were straitified into five groups:① OSAS（AHI 5-20 beats/h）with hypertension group（n= 22）;② moderate and severe OSAS with hypertension group（n=58）:OSAS（AHI＞20 beats/h）with hypertension; ③ hypertension alone group（n=20）;④ OSAS alone group（n=16）:moderate and severe OSAS（AHI＞20 beats/ h）;⑤ normal control group（n=20）:healthy person without OSAS or hypertension.The serum level of IL-6, sCD40L,hsCRP,sICAM-1,VACM-1 are determined by ELISA method.Results The serum level of IL-6, sCD40L,hsCRP,sICAM-1,VCAM-1 in patients of OSAS alone group or HT alone group is higher than that of normal control group;whereas,the serum level of IL-6,sCD40L,hsCRP,sICAM-1,VCAM-1 in patients with hy- pertension co-existed OSAS are furthermore higher than that of OSAS alone group,hypertension alone group（P＜ 0.05）;The serum level of hsCRP,sICAM-1,VCAM-1 are positively related with AHI and decreased SaO₂（r= 0.852,P＜0.01）.Conclusion Inflammatory factors were associated with pathogenesis of hypertension in patients of obstructive sleep apnea syndrome.OSAS potentially aggravate hypertension via infammatory reaction.