Endoscopy has been increasingly used in clinical practice and as a standardized examination procedure forgastrointestinal diseases. However, only a few studies on endoscopic screening for evaluating mortality reductionfrom gastric cancer have been carried out. Even if a high detection rate is obtained in clinical practice, such a ratecannot be directly accepted as evidence providing the effectiveness of cancer screening. Endoscopic screening forgastric cancer is not an exception of possibility to detect overdiagnosis. If detection rate is used for the evaluationof the effectiveness of cancer screening, the possibility of overestimating the effectiveness of cancer screeningcannot be ruled out. To avoid the effect of overdiagnosis and confirm the effectiveness of endoscopic screening,mortality reduction from gastric cancer must be carefully evaluated by conducting reliable studies. The burdenof gastric cancer remains real and this cannot be ignored in Eastern Asian countries. To determine the bestavailable method for gastric cancer screening, evaluation of its effectiveness is a must. Endoscopic screeningfor gastric cancer has shown promising results, and thus deserves further comprehensive evaluation to reliablyconfirm its effectiveness and how its optimal use can be strategically promoted.