The relationships between various psychosocial factors and blood pressure were examined in a probability sample of the adult population of the state of Michigan in 1980-1983. Excluding individuals diagnosed by a physician as having high blood pressure and controlling for the major risk factors for hypertension, a number of psychosocial factors significantly predicted blood pressure. Among both men and women, those who generally did not express their emotions (including anger) and who harbored grudges and aggressive impulses had higher diastolic blood pressure. Among men only, those with low self-confidence and less perceived control over their lives had higher systolic and diastolic blood pressures. Those who reported poorer mental health had higher diastolic blood pressure. Among women only, those who rated their relationships with family and best friend more poorly had higher systolic blood pressure. Possible explanations are discussed for the gender-specific relationships between blood pressure and certain psychosocial factors.