Cranial electrotherapy stimulation (CES) is beneficial in reducing anxiety in psychiatric patients. However, no studies have reported on elderly patients with generalized anxiety disorders (GAD). This study aimed to determine the efficacy and safety of a 6-week CES intervention for late-life GAD. This single-arm pilot study assessed 6-week CES treatment (Alpha-Stim AID) for late-life GAD and 4-week follow-up post intervention. The Hamilton Rating Scale for Anxiety (HAMA) and Beck Anxiety Inventory (BAI) were used as baseline and outcome measures at weeks 4, 6, and 10, respectively. Treatment response was defined as 50 % or more reduction of the HAMA score and remission was defined as a of score ≤7 on the HAMA. Other measures included depression, sleep quality, and quality of life assessment. We included participants (n = 27) aged 68.0 ± 5.0 years, 81.5 % of whom were female. Fifteen (55.6 %), 18 (66.7 %), and 15 (55.6 %) patients were concurrently treated with antidepressants, BZDs, and antipsychotics, respectively. Intention-to-treat (ITT) analysis revealed a significant decrease in HAMA scores from baseline (20.96 ± 3.30) to week 6 (12.26 ± 7.09) and one-month (12.85 ± 7.08) follow-up at W10 (all p < 0.001). The response and remission rates were 33.3 %, 40.7 %, and 48.1 % and 25.9 %, 29.6 %, and 25.9 % at W4, W6, and W10, respectively. The CES improved depression and sleep conditions as measured by the Beck Depression Inventory-II and Pittsburgh Sleep Quality Index. CES clinically reduces symptoms of anxiety and depression and may improve sleep quality in late-life GAD. Future randomized controlled study is needed.