Fibrinous pleurisy, also known as dry pleurisy, is seen in diseases such as pneumonia and tuberculosis. Fibrinous pleurisy is the exudation of fibrinogen on the surface of the pleura, followed by the formation of fibrin, or fibrin. The exuded fibrin adheres to the surface of the pleural cavity and is pulled into a fluffy shape during respiratory movements, which is manifested by chest pain. In advanced cases, the fibrin cannot be dissolved and absorbed in time, and mechanization may occur, limiting respiratory movements. In lobar pneumonia, fibrinous inflammation occurs in the lung tissue, exuding a large number of fibrin and neutrophils; in tuberculosis, direct infection by Mycobacterium tuberculosis or metabolites entering the pleural cavity can cause tuberculous pleurisy, with fibrin exudation in the early stage. Fibrinous pleurisy is recommended to consult a doctor in time, after clarifying the cause of the disease, to carry out symptomatic treatment for the cause.