Purpose: The purpose of this study was to examine the relationship among cognitive function, depression, social support, and self-care in elderly with hypertension. Methods: The subjects were 132 elderly with hypertension living in Seoul, Korea. Data were collected through face-to-face interviews using the Korean version of Mini-Mental State Examination(MMSE-K), Short form geriatric depression scale, social support questionnaire 6, and hypertension self-care scale. Results: Thirty-four percent of the subjects had questionable dementia and forty-two percent of the subjects were depressed. Means for social support were 2.40 for network size and 4.07 for satisfaction. The mean score of hypertension self-care was 60.34, indicating that the subjects took care of themselves moderately well. Cognitive function was negatively related to depression. Social support network and satisfaction were negatively related to depression. Self-care was negatively related to social support network. Conclusion: Programs are needed for elderly with hypertension to improve their cognitive function, depression, and social support. Also further studies are needed to confirm the factors related to self-care in the elderly with hypertension.