Hyponatraemia is one of the most common electrolyte disturbances in clinical practice, serum sodium concentration <135 mmol/L is diagnosed with hyponatraemia, and the majority of chronic hyponatraemia are prone to be ignored or misdiagnosed by clinicians due to its mild symptoms or being covered by primary diseases. Accurate diagnosis and timely treatment can reduce mortality, shorten the length of hospital stay, and improve the quality of life. Its treatment mainly focuses on allevaiating the etiological factors. For the patients with syndrome of inappropriate antidiuretic hormone secretion (SIADH), limit of water, hypertonic saline, V2 receptor antagonist and other comprehensive treatment should be considered. In this article, we reviewed the progress of diagnosis and treatment of hyponatraemia.