Gastroesophageal reflux disease (GERD) is a common digestive disorder that usually has symptoms including reflux, heartburn, pain when swallowing, etc. Evolving from traditional needle acupuncture and electroacupuncture (EA), transcutaneous electrical acustimulation (TEA) becomes a popular method for treating GERD with its non-invasive intervention feature. Recently, an even more effective method synchronized with respiration in TEA is emerging. However, the current procedure for conducting synchronized TEA (STEA) treatment is mostly based on patients’ manual synchronization, which can generate a big delay or error in the synchronization, significantly compromising the effectiveness of this method. To solve this issue, this research presents a novel STEA device that can automatically detect the user’s respiration wave and synchronize with the breath to conduct TEA. With this automated synchronization device, the patients can inhale and exhale with an uninterrupted and normal respiration pace while receiving the TEA treatment, largely simplifying the treatment procedures and enhancing the effectiveness of the method. The system of the STEA device consists of a chest strip respiration sensing element, a stimulation point identifier, and a stimulation current generator. Experiments were conducted to verify human respiration detection, electrical current generation and synchronization. The results demonstrated the feasibility, effectiveness and reliability of the automated device system.