The relatively high incidence of gastric cancer in Taiwan warranted the need of a disease-specific quality of life (QOL) instrument. We translated the EORTC QLQ-C30 and QLQ-STO22 according to the guidelines from the EORTC. A total of 100 patients were interviewed. Convergent and discriminant validity, Cronbach's alpha coefficient and known-groups comparisons were used to examine the reliability and validity. We found good reliability for multi-item subscales of the QLQ-C30 and QLQ-STO22 (Cronbach's alpha coefficient: 0.70–0.94) except cognitive functioning of the QLQ-C30 and eating restriction of the QLQ-STO22. Patients in the active treatment group experienced compromised functional status and worse treatment-associated symptoms than those in the follow-up group. Similar results were found in comparisons based on Eastern Cooperative Oncology Group (ECOG) Performance Status and dysphagia grades. The study has ascertained the cross-cultural validity, reliability and clinical applicability of the Taiwan Chinese version of the EORTC QLQ-C30 and QLQ-STO22. Copyright © 2007 John Wiley & Sons, Ltd.