Objectives: The purpose of this study was to evaluate the effectiveness of Korean medicine treatments in alleviating symptoms of dry mouth, with a specific focus on Yin deficiency.Methods: A 50-year-old female patient diagnosed with xerostomia was treated using Korean medicines, aimed at addressing Yin deficiency. The assessment included both subjective and objective measures. For subjective measures, we used the Yin Deficiency Questionnaire (YDQ) to diagnose and assess the Yin deficiency symptoms and the Dry Mouth Symptom Questionnaire (DMSQ) to evaluate the severity and frequency of dry mouth symptoms. For objective measures, we used the Oral Moisture Checking Device (Mucus®) to measure oral moisture levels. Additionally, we measured the heart rate variability (HRV) to assess the autonomic nervous system, focusing on indicators related to the parasympathetic nervous system.Results: We observed improvements in the patient’s symptoms. The Visual Analog Scale (VAS) scores improved for all questions on both DMSQ and YDQ questionnaires. Additionally, the measurements taken with Mucus increased, and the HRV test indicators related to the parasympathetic nervous system showed improvement.Conclusion: Korean medicine treatment could be an effective and quick method for treating dry mouth symptoms.