Objective： To study diagnostic valuation of proton magnetic resonance spectroscopy on patients with minimal hepatic encephalopathy Methods： MRS of cingulated cortex and prefrontal lobe were acquired using PRESS sequences in Thirty-three patients with MHE and forty-six patients without MHE and 30 controls. Peak area of each metabolite, including NAA , Cr , Cho , MI , Glx and their ratios to Cr were computed , respectively. Then compared with the controls，Venous ammonia was measured in 33 patient s with MHE. Results： Compared with controls , patients with MHE showed significant decreased Cho/ Cr , MI/ Cr and significant elevated Glx/ Cr in cingulate cortex and prefrontal lobe . Glx/ Cr and Cho/ Cr were significantly different in patients without and with MHE (P0.05). MI/ Cr were significantly different in patients without MHE and the control group (P0.05)。 The results also showed a significantly positive correlation between Glx/Cr in both cingulate cortex and prefrontal lobe and the venous ammonia concentration and a significantly negative correlation between Cho/Cr and MI/Cr and the venous ammonia concentration. Conclusion： patients with MHE showed significant decreased Cho , MI and significant elevated Glx in cingulate cortex and prefrontal lobe on MRS ； The results also showed a significantly correlation between metabolite changes in both cingulated cortex and prefrontal lobe and the venous ammonia concentration， diagnostic valuation of MRS was significant to MHE； cingulate cortex and prefrontal lobe might be a sensitive location in detecting MHE .