Case: The patient, female, 60 years old, weighing 80 kg, had recurrent asthma attacks for more than 50 years, with frequent attacks in recent years, usually treated with long-term inhalation of salmeterol ticarbazone (sulforaphane 250) 1 inhaled bid + slow-release theophylline 0.1 bid + shun 10 mg qn, still with recurrent asthma attacks and significant wheezing at night. Repeated oral or intravenous glucocorticoids were used for asthma exacerbation. Pulmonary function test was moderate obstructive ventilatory dysfunction and positive bronchodilator test. Allergen skin test was strongly positive for dust mite and strong positive for house dust mite. The diagnosis was bronchial asthma, chronic and persistent, uncontrolled. the ACT score was 8. During the outpatient follow-up, the patient was considered to have refractory asthma. In order to find the cause of refractory asthma, the patient carefully pursued the medical history and complained of frequent heartburn, acid reflux and belching due to long-term oral glucocorticoids, so the patient was considered to have possible gastroesophageal reflux, which aggravated his asthma symptoms that were difficult to control. Therefore, on the basis of the original asthma treatment, the patient was given the acid regulator omeprazole 20 mg bid diagnostic anti-reflux treatment. After 1 month of treatment, the patient’s asthma symptoms improved and the number of nocturnal attacks decreased significantly. Omeprazole anti-reflux therapy was continued and at six months follow-up, there were no acute asthma attacks and the ACT score improved to 22. Gastroesophageal reflux disease (GRED) is a disease that causes a series of symptoms or complications due to reflux of gastric contents into the esophagus. It can cause typical esophageal symptoms such as retrosternal burning sensation, retrosternal pain sensation, and acid reflux, and can also cause extraesophageal symptoms such as reflux cough syndrome and reflux asthma syndrome. The relationship between GERD and asthma was recognized as early as 1892 when Osler suggested that asthma patients should not eat too much dinner to avoid asthma attacks, and in 1976, Mays proposed “gastric asthma”, which refers to asthma caused by GERD. The incidence of GERD in asthma patients is 30-75%, which is significantly higher than that of the general population (5-8%), and the incidence of asthma in GERD patients is also significantly higher than that of non-GERD patients. GERD can induce or aggravate asthma, and GERD patients can directly damage the bronchial mucosa epithelium due to repeated micro-inhalation of gastric contents, which stimulates the vagal nerve receptors in the airway and causes airway contraction; at the same time, the acidic gastric contents entering the esophagus stimulates the mucosal receptors in the lower and middle esophagus, which acts on the vagal nerve endings and forms the esophageal bronchial reflex or laryngobronchial reflex, leading to an asthma attack. This leads to an asthma attack. The recurrent asthma attacks and asthma medication aggravate GERD, thus forming a vicious circle. In addition to asthma symptoms, patients with asthma combined with GERD often have reflux symptoms such as retrosternal burning sensation, retrosternal pain, acid reflux and belching, which should be clinically recognized and paid attention to. The diagnosis of GERD is based on: 1. typical reflux symptoms: such as retrosternal burning sensation, retrosternal pain, acid reflux, belching, etc. 2. 24-hour pH monitoring of the esophagus: Demeester score R12.70, and or SAPR75% . For patients without typical reflux symptoms, this test can be chosen to help confirm the diagnosis of GERD. a positive result of this test is more significant, a positive result can confirm the diagnosis of GERD, while a negative result cannot exclude GERD. 3. diagnostic treatment with proton pump inhibitors (PPI): for patients with reflux symptoms, PPI drugs such as omeprazole 20mg twice daily for 2-4 weeks are given. Improvement of reflux symptoms and asthma symptoms can confirm the diagnosis. For patients without obvious reflux symptoms, if there is clinical suspicion that GERD may exist, PPI diagnostic treatment can also be given, and if the related symptoms improve, GERD can also be diagnosed. 4. Endoscopy: It can detect related lesions in the esophageal mucosa. GERD is one of the triggers of refractory asthma. For refractory asthma, while treating asthma, we must look for possible triggers and treat them at the same time in order to control asthma. In the case of the aforementioned patient, the asthma could not be controlled despite the use of a large number of asthma control medications, and the asthma was only controlled after the patient was given the appropriate acid control treatment in consideration of the possible presence of GERD. It should also be emphasized clinically that for the diagnosis of GERD, if 24-hour pH monitoring of the esophagus is not available or its result is negative, PPI diagnostic therapy can be given.