The influences of various antihypertensive agents on the renal function and blood pressure of the old ages over 60 years old with hypertension at an almshouse were hourly and daily observed. And the results were as follows. 1. Each antihypertensive agent showed a respectable descending effect of blood pressure on them. 2. In the cases treated with serpetin, the change of GFR and RPF was not evidnetly observed, but the fall and drop of RVR was observed. 3. The increasion of RPF and RBF, and the decreasion of FF and RVR were observed in the cases treated with aprezoline. 4. In the cases treated with methobromin, the decreasion of RVR was generally observed on the descent of blood pressure, but the decreasion of RPF and RBF was also observed in the mean number. 5. In the cases treated with ansolysen, the tendency of their appearance was not abrupt. 6. In the cases treated with trapon, the change of GFR and RBF was not showed having an tendency and the sume decreaslon of RVR was observed. 7. Most of cases had no differences on the subjective symptoms and the findings of urin between the period before and after the use of antihypertensive agents, and some of cases showed an aggravation. 8. Since the above results, the reaction of renal function on the old age with hypertension had no essential difference with the each decade and the effects of these antihypertensive agents were expected, but the kidney of the old age had a possibility of falling into a unfavourable condition on the abrupt decent of blood pressure.