Objective To observe the effects of different bicarbonate ion concentration dialysate on hemodialysis patients blood gas. Methods Thirty-two maintenance hemodialysis patients were treated for 3 months respectively with common bicarbonate dialysate（HCO3- 34mmol/L）and linear regulating bicarbonate ion dialysate in which the HCO-3 concentration decreased from 38mmol/L to 34mmol/L in 3 months. They were also examined the blood gas、BUN、Scr、K+、Na+、Cl-、Ca2+ and electrocardiogram before and after hemodialysis, and they were also recorded the side effections during the treatment. Results The blood gas of the patients treated with common bicarbonate dialysate had no significant changes at beginning and 3 months later (P>0.05). While treated with the patients BE(b)、BE(ect) before and after hemodialysis had significantly improved (P<0.01) with the treatment of linear regulating bicarbonate ion dialysate, but pH、HCO3-、PO2、PCO2 had no significant changes ( P>0.05). Conclusion With the linear regulating bicarbonate hemodialysis, the patients can obtain enough HCO3-. While eliminating the metabolic waste materials, it can effectively correct the patients' acidosis. When the hemodialysis finished, the HCO3- concentration in dialysate may decline gradually to common 34mmol/L. Therefore it avoided the alkalosis and hypoxemia that the patients may be occured after hemodialysis.