[en] Acutal condition of mass gastric survey was studied, and gonadal-, marrow- and surface doses were measured using a body phantom. A total number of people who were given x-ray examination in 1975 was 86,125. It means that an average number of x-ray examination per a person is 0.0324, or one out of 30 persons undergoes x-ray examination annualy. Roentgenography and TV fluoroscopy examination are performed using equipments such as mirror camera and image intensifier in 1976. Doses given to patients differ according to the equipments used. Surface dose given by one roentgenography is 0.74 and 0.17 rad when the mirror camera and image intensifier is used, respectively. A total dose including gonadal and marrow doses by image intensifier decreases to 1/5 - 1/10 of that by mirror camera. There is no significant difference of doses between screen fluoroscopy and roentgenography when the mirror camera is used, but dose given by TV fluoroscopy is approximately 1/100 of that by screen fluoroscopy. Dose to patients given by one gastric survey is a total dose by both roentgenography and fluoroscopy, and this is much higher than that by direct roentgenography or mass thoratic survey. Ten rem of surface dose is equivalent to the dose given at short distance from A-bomb explosion in Hiroshima. Marrow dose, however, is as low as 0.5 rem. (Iwagami, H.)