Connective tissue disease is a general term for diseases involving connective tissue (fat, blood vessels, bones, etc.). It is a generic term for a group of autoimmune diseases in which chronic inflammatory pathological changes in blood vessels and connective tissue are the underlying pathology, and mucinous edema and fibrinoid degeneration in loose connective tissue are the basic pathological changes, and the lesions involve multiple systems. The clinical manifestations of connective tissue disease include rheumatic disease symptoms, rash, arthralgia, muscle pain, alopecia, photosensitivity, Raynaud’s phenomenon, oral and vulvar ulcers, dry mouth and eyes, parotid enlargement, and other system-specific lesions such as digestive, respiratory, urinary, neurological, and hematological systems. Since connective tissue disease is a general term for a variety of diseases, the clinical manifestations of various classifications vary and need to be combined with medical history, specific manifestations and laboratory tests to clarify the specific disease classification. The most common clinical ones are rheumatoid arthritis, systemic lupus erythematosus, polymyositis, dry syndrome, gout, etc. After the disease is identified treatment measures include general treatment (education, lifestyle, exercise, etc.), pharmacological treatment (non-steroidal drugs, glucocorticoids, anti-rheumatic drugs, immunosuppressive drugs, atopic drugs, etc.), and surgical treatment (orthopedic, synovectomy, joint replacement, etc. for irreversible joint changes). Connective tissue diseases are non-self-curing, irreversible diseases, early detection, early diagnosis and early treatment will lead to a good prognosis.