The aetiopathogenesis of essential hypertension has been more intensively investigated in recent years mainly in genetic high-risk groups and patients with transitory and early forms of essential hypertension. A group of 29 patients with mild hypertension according to the WHO criteria were submitted to hypertensiological, psychological and psychophysiological specification in this study. Twenty-four hour blood measurements were performed for this purpose. The group could thus be divided into 18 patients with white-coat hypertension (WH) and 11 patients with real mild hypertension (H). Contrary to expectations, mild hypertensives had weaker systolic (p < 0.05) and diastolic (p < 0.01) blood pressure reactions to mental stress than white-coat hypertensives. Their cardiovascular recovery was not reduced after stress. Psychological differences between the groups were only found with respect to irritability (FP1: H 6.9 sd 2.1, WH 5.2 sd 2.1 stanine) and hypertensives compared to the reference random sample on the FPI scale emotional instability (6.5 stanine). Other psychosomatic studies should replicate the results obtained in this study in larger patient populations with white-coat and mild hypertension.