Abstract: Objective To explore the effect of diet intervention on erythro cyte intracellular free calcium concentration (Ca²⁺)i in subjects with impaired glucose tolerance(IGT).Methods Diet intervention trial was carried out in 42 subjects with IGT.The experiment period was 10 months.The erythrocy te Ca²⁺i,fasting serum glucose(FSG),2-hour serum glucose after 75g OGTT(2HSG),trigly ceride(TG),cholesterol(TC),glycosylated low density lipoprotein(G-LDL)of serum as well as body mass index(BMI)were observed on 2 occasions,before and 10 months after initiation of a diet intervention trial.Results The erythrocyteCa²⁺i in subjects with IGT was increased significantly compared with that of normal.The erythrocyteCa²⁺i,FSG、2HSG、TG、TC、G-LDL levels as well as BMI decreased significantly in 42 subjects with IGT following diet intervention(P<0.01).Conclusion The results suggest that diet intervention inhibits significantly the increase of erythro cyteCa²⁺i and the above change might be associated with the decrease of serum glucose caused by the diet intervention.