Abstract：Acute exercise-associated hyponatremia in athletes often occurs during the competition or training season for endurance events such as the Marathon, Iron Man Triathlon and Ultra-marathon. Acute hyponatremia arises from complex contributing factors, but is always fatal. The major risk factors of acute hyponatremia in athletes is the dramatic loss of electrolytes caused by profuse sweating followed by rapid intake of excessive amounts of amount of water without electrolytes. The purpose of this study was to review the current studies about mechanism, treatment and the prevention of acute hyponatremia and to provide coaches and athletes with correct procedures for hydration after high-intensity or endurance training. This article can also provide the references for our study to develop the preventive sport drinks. (Full text)