By investigating the effect of habits and surroundings on the blood pressure (of hypertensives) in Okayama Prefecture, the following results were obtained: 1. There was a close relation between drinking of alcoholic beverage and blood pressure but this concerned with men who acquired the habit of drinking by the force of surroundings. Strong tea and coffee, too, had something to do with blood pressure but in this case the surroundings were out of question. 2. Blood pressure was apt to rise with men who took meals hastily but it bad nothing to do with women. 3. Those who were fond of excessively salty or fatty food often suffered from hypertension. 4. Those who were particular about their food were found in the greatest number among the group of extreme hypertension. 5. Hypertension was rarely found among those with constant poor appetite. 6. Hypertension seldom attacked those who had the following complaints: To fall ill occasionally, to be always out of order, to have severe mental fatigue, to feel fatigue every morning, etc. But hereditary weak constitution had nothing to do with hypertension. 7. The blood pressure rose when the time for sleeting was less than 4 hours. It also rose with those who were easily awakened from their sleep or could not enjoy a sound sleep. But it was difficult to find any immediate relations between the failure to sleep readily or to have regular hours for sleep and the blood pressure. 8. Many heavy smokers were found among hypertensives which shows that smoking is the cause of high blood pressure. 9. The blood pressure rose of women whose household operates less than 50 area of farms while in the household with over one hectares, men's pressure rose. This is because in the former case, the stress of labor falls on women while in the latter, men bear the burden. 10. The rate of grey hair and baldness was high with the group of hypertension irrespective of sex. The same was the case with the declining of memory.