Abstract： Objective To discuss the method of nursing intervention on taking medicine at selected timefor guiding " non - dippers" or " deep - dippers" in patients with primary hypertension in order to improve therapeutic effect. Methods Leading to compliance with doctor's advice, 40 hospitalized cases were taken medicine at different time, the patients in control group were received routine treatment while the others in experimental group were received individualized medication at selected time. Results In experimental group, the effect of renewing normal circadian blood pressure rhythm was obviously superior to that of control group (P<0.05) . Conclusions When treating " non- dippers" or " deep- dippers" in patients with primary hypertension, there appears to be significances on improving anti -hypertensive effect by nursing intervention on individualized medication at selected time.