Background and Aims. Age cutoff is an important factor in deciding whether esophagogastroduodenoscopy (EGD) is necessary for patients presenting with upper gastrointestinal symptoms. However, the cutoff value is significantly different across populations. We aimed to determine the age cutoff for EGD that assures a low rate of missing upper gastrointestinal malignancy (UGIM) and to assess the yield of prompt EGD in Vietnamese patients presenting with upper gastrointestinal symptoms. Methods. All EGDs performed in outpatients during a 6-year period (2014–2019) at a tertiary hospital that provided an open-access endoscopy service were retrospectively reviewed. Repeat or surveillance EGDs were excluded. Different age cutoffs were evaluated in terms of their prediction of the absence of UGIM. The yield of endoscopy to detect one malignancy (YoE) was also calculated. Results. Of 472,744 outpatients presenting with upper gastrointestinal symptoms, there were 2198 (0.4%) patients with UGIM. The median age and male-to-female ratio of patients with UGIMs were 57.9 ± 12.5 years and 2.5 : 1, respectively. The YoEs in patients <40, 40–60, and >60 years of age were <1, 1–10, and >10 per 1000 EGDs, respectively. The age cutoffs of 30 years in females and 35 years in males could detect 98.2% (95% CI: 97.7%–98.8%) of UGIM cases with a YoE of about 1 per 1000 EGDs. Conclusions. The age cutoff for EGD in Vietnamese should be lower than that recommended by current international guidelines. The strategy of prompt EGD showed a low YoE, and its cost-effectiveness requires further investigation.