Background: This study developed a Japanese version of the Geriatric Anxiety Scale (GAS‐J) and its short form (GAS‐10‐J) to evaluate anxiety in Japanese older adults and assess its psychometric properties using a cross‐sectional design. Methods: A total of 331 community‐dwelling older adult participants (208 men, 116 women, seven unknowns; mean age = 73.47 ± 5.17 years, range = 60–88 years) recruited from two Silver Human Resources Centres in the Kanto region, Japan, answered a set of self‐report questionnaires. Of these respondents, 120 participated in a follow‐up survey to evaluate test–retest reliability. Results: Confirmatory factor analysis suggested that, as with the original GAS, the GAS‐J had a three‐factor structure and the GAS‐10‐J had a unifactor structure with high standardised factor loadings. Test–retest correlations and internal consistency analyses indicated that these scales were reliable. Correlations between the GAS‐J/GAS‐10‐J with the Geriatric Anxiety Inventory, Generalised Anxiety Disorder‐7, Geriatric Depression Scale‐15, World Health Organization‐Five Well‐Being Index, and Kihon Checklist were mostly consistent with our hypotheses, thereby supporting the construct validity of the GAS‐J/GAS‐10‐J. Conclusions: The findings indicate that the GAS‐J and GAS‐10‐J have robust psychometric properties for assessing late‐life anxiety in Japanese older adults. Further GAS‐J studies are required for clinical groups. [ABSTRACT FROM AUTHOR]