To investigate ghrelin level change in combination with psychological stress in the hypertensive old people with cognitive impairment and to explore its effect as well as possible mechanism. The study population of 300 elders was divided into 2 groups, 148 with hypertension and 152 non-hypertension, who were screened for psychological distress and cognition function, and had blood drawn to measure plasma levels of ghrelin and total cortisol on the same day. The rates of anxiety and cognitive impairment were higher in the hypertension elders, which were negatively correlated with plasma ghrelin level, resulted from chronic cortisol response to anxiety. Chronic plasma cortisol increase to long-term anxiety leads a reduce in ghrelin level which then adversely affects blood pressure and cognitive function in old people. So measuring ghrelin of elders may be a diagnostic tool to predict cognitive development and ghrelin may be a selective antihypertensive medicine for cognitive impairment elders with or without chronic psychological stress.