Gastric occult blood screening has been performed for 242296 persons from 1986 to 1993. 30227 persons had positive reactions to the occult blood reagent. Among them, 17915 persons were asked to accept gastroscopy exam, and 638 esophageal-gastric cancers were found. The cancer detection rates were 3.56%. 4774 persons were asked to accept screening twice and 203 persons were asked to accept screening three times. After follow-up, the cancer detection rates were 2.11% for occult blood positive group if the screening was conducted once a year. The missing case was 0.77% for negative group and it was 0.05% in the same group if the screening was performed twice. Lastly, the missing case would be decreased to 0% when the patients undergone the exam, for three times in continuity. Two thirds of patients still belonged to the early-middle stage of cancer. The 5-year survival rates were 95.2%. The missing case of cancer would be reduced to 0% if the screening was conducted for three years in continuity. The death rates were deducted as well. It is certified that this method is the most effective and reliable way for reducing the death rate of cancer and screening of the upper digestive tract cancer.