The normal value of G-6-PD enzyme activity is 2.5-5.8KU/L in our hospital, <2.5KU/L can be diagnosed as lack of G-6-PD enzyme activity. However, there is no certain standards for the definition of mild deficiency, moderate deficiency and severe deficiency in our hospital. It was reported that activity is less than 10% of normal is severe deficiency, less than 10%-60% of normal is moderate deficiency, less than 60% of normal is mild deficiency.