Conceding that a great progress of cancer researches is opening up a new phase in the treatment of cancers and realizing an early operation is at the present a sole approach to the gastric-cancer therapy, an early diagnosis seems to be the most important, daily clinical problem we have to face. In view of this we have attempted to grasp the true nature of gastric-cancer patients by a series of epidemiologic and symptomatologic observations statistically on the hospitalized patients during the past 12 years, and outpatients for the past 2 years of our clinic. From our observations we find that the most likely ages of the onset of cancers range from 50 to 60, and that the gastric cancer developing at an early age is found more predominantlyin female. Moreover, in the farm districts, the proportion of female patients far surpasses that of any other occupation. Of all the cancer cases treated during the 12-year periods, the gastric cancer occupied 45 per cent. Of all the outpatients during the two-year periods, 27.8 per cent proved to be suffering from digestive organs; and the gastric cancer cases occupied 5.7 per cent of the latter. Now, it is impossible, simply by its symptoms, to differentiate the gastric cancer from such diseases as the gastric and the duodenal ulcers, and gastritis; as the symptom and chief complaint of the patients at its onset are epigastric pain, the foremost, followed by feeling of full and tension in the epigastrium, and eructation and heart burn, and since all of these have practically no distinguishable difference from those of the latter. Of the total patients, the cases impossible of operation reached as high as 39 per cent while those being operated on but ending only in laparotomy proved to be 15 per cent, and the ones on whom the gastric resection had proved a success were merely 8.8 per cent. It is, moreover, interesting to note that despite as high as 75.8 per cent of the cases having palpable abdominal tumors at the time of admission, the ones whose Virchow's gland and other lymphatic glands had been palpable were extremely little: no more than 0.6 per cent. The occult blood reaction of stool was positive in 71 per cent, and 18 per cent of gastric cancer patients were of either normal or hyper acidity; and 61 per cent of the total had abnormal defecation (constipation, diarrhea, etc.). As for complications, helminthiasis is predominant (30%). This fact is worthy of an attention, for symptoms resulting from helminth's attacks often obscure those of gastric cancer. Reviewing the statistical data so far mentioned, we realize keenly how little early diagnosis of gastric cancer is being carried out and how difficult it is to carry this out; at the same time we have learned, on the other hand, how essential and beneficial it is to grasp epidemiologic and symptomatologic problems for its diagnosis.