Abstract: Objective: To confirm an unknown Peak（Pu) in the permanent focal cerebral ischemia of cats with 1 H MRS, study its pathological changes and conjecture its applicatio n value in future Methods: After focal cerebral ischemia, diffus ion weighted imaging（DWI) was used to identify regions of ischemia for 1 H MRS voxel localization Meanwhile, the stereotaxic atlas of the cat brain was referred 1 H MRS was used to monitor the progression of focal cerebral ischemia in 6 cats over a period of 7 days following middle cerebral artery oc clusion Lactate, NAA, choline, creatine, and Pu were obtained The time course and cerebral areas that the Pu was detected w ere studied emphatically Meanwhile, the hematoxylin and eosin staining was use d to reveal the pathologica changes, and the pathologica bases of Pu were guesse d Results: In the affected regions, lactate was elevated a lmost immediately after the onset of cerebral ischemia, and NAA began to decline within several hours of acute infaction The Pu in the δ 1 2 region was cons istently detected in the affected cerebral areas from 2 days to 7days after MCAO The time when Pu could detected the neurons had died completely in the affect ed cerebral areas Conclusion: Pu has a close relationship with cerebral ischemia necrosis It may be a intrinsic production of the necrotic t issue, can be taken as a specific marker, and has vary important clinic applicat ion value