The limited thickening of the pleura that occurs during the treatment of pleurisy is mainly due to local tissue fibrosis and adhesions caused by inflammatory stimuli. The main cause of pleurisy is infection, and the most common pathogens are Streptococcus pneumoniae, Staphylococcus aureus, and Mycobacterium tuberculosis. Infection leads to pleural edema, exudation and pleural effusion, and failure to recover from inflammation leads to pleural fibrosis and adhesions, which in turn leads to pleural thickening. Especially in tuberculous pleurisy, pleural thickening will be more obvious, accompanied by obvious pleural adhesions and calcification. Pleural thickening can cause chest pain and discomfort. The faster the recovery from pleurisy, the less obvious the pleural thickening will be, and after pleurisy occurs, standardized treatment should be carried out under the guidance of clinicians to avoid chronic inflammation as much as possible.