Based on pathophysiology, pulmonary oedema can be divided into two main categories. The first is cardiogenic pulmonary oedema, also known as hydrostatic pulmonary oedema, which is caused by an increase in pulmonary capillary hydrostatic pressure from various causes; the second is non-cardiogenic pulmonary oedema, which has a wide range of causes and a complex pathogenesis. Depending on the cause, it can be divided into neurogenic pulmonary oedema, plateau pulmonary oedema, infectious pulmonary oedema, post-relaxation pulmonary oedema, drug-related pulmonary oedema and toxic pulmonary oedema.