Tuberculosis is a common infectious disease that is not usually self-testable and requires a doctor to diagnose it with a combination of symptoms, signs, and tests. TB is usually spread by droplets containing Mycobacterium tuberculosis in the air through coughing, sneezing, loud talking or laughing. People with low immunity are particularly susceptible, such as the elderly, infants and young children, the weak, malnourished, and those with chronic diseases. Tuberculosis can be diagnosed mainly by the following ways: 1. Observation of symptoms: The clinical symptoms of patients with tuberculosis are mainly respiratory and systemic symptoms. Respiratory symptoms such as cough, coughing for more than 2 weeks or blood in the sputum, dry cough, increased sputum, irritating cough, hemoptysis, chest pain or even dyspnea can be suspected. Patients may also have systemic symptoms, typically a low-grade fever, usually rising in the afternoon and falling the next morning. It may also be accompanied by malaise, night sweats, loss of appetite, weight loss, etc. Women may also have symptoms of menstrual disorders; 2. Imaging: Imaging chest x-ray examination can make a routine diagnosis of pulmonary tuberculosis. It helps to determine the location, shape, and relationship with surrounding tissues of the lesion, and can effectively show whether there is a lesion in the lung and the extent of the lesion. Among them, inactive TB examination results show calcification or fibrosis, which is usually asymptomatic, while active TB may show patchy shadows with blurred edges and may have a central cavity; 3. Sputum smear examination: Sputum smear examination is the main way to confirm the diagnosis of TB, and can be performed by collecting sputum specimens for bacterial examination. By examining the patient’s early morning sputum, nocturnal sputum or immediate sputum, it can determine whether the patient presents with tuberculosis; 4. Nucleic acid amplification test: detecting specific target RNA or DNA sequences after amplification by nucleic acid probes significantly improves the detection rate of tuberculosis bacteria in sputum with higher sensitivity and specificity and faster speed, which is an important modern method for confirming tuberculosis. In addition, there are other tests such as fiberoptic bronchoscopy, tuberculin test, and gamma interferon release test that can also help in the diagnosis. Patients who develop common symptoms that are suspected of TB need to seek medical attention and follow the doctor’s advice for relevant tests to clarify the diagnosis. If tuberculosis is diagnosed, patients should protect themselves well and undergo targeted treatment under the guidance of a doctor. Patients should maintain emotional stability, early detection and early treatment to help the recovery and prognosis of the disease.