Background:　A　better　understanding　the　mechanisms　of　cerebral　ischemia　is　important　both　for　diagnosis　and　treatment.Objective:　The　study　aimed　to　quantify　several　characteristics　of　magnetic　resonance　imaging　(MRI)　and　magnetic　resonance　spectroscopy　(MRS)　to　indicate　the　brain　tissue　changes　at　different　stage　of　cerebral　ischemia　in　rats.Methods:　In　the　present　study,　a　rat　model　of　cerebral　ischemia　was　established　by　middle　cerebral　artery　occlusion　(MCAO)　in　the　left　hemisphere.　MRI　and　MRS　were　performed　on　15　Sprague　Dawley　rats　4　H,　24　H,　and　1W　after　MCAO.　Apparent　diffusion　coefficient　(ADC),　relative　ADC　including　FNR,　PNR,　PNF,　and　metabolite　ratio　NCC　were　proposed　to　reflect　the　changes　of　water　diffusion　and　metabolism　in　brain　tissue.Results:　ADCs　of　focal　zone　and　penumbra　zone　from　1W　group　were　significantly　larger　than　those　from　4H　group,　respectively　(both　p＜0.05).　PNR　and　PNF　of　24H　and　1W　groups　were　significantly　less　than　4H　group　(all　p＜0.01).　NCCs　of　focal　zone　and　penumbra　zone　were　significantly　less　than　the　normal　zone　within　4H,　24H,　and　1W　groups,　respectively　(both　p＜0.01).　While　NCCs　of　penumbra　zone　from　24H　and　1W　groups　were　significantly　larger　than　4H　group　(both　p＜0.01).Conclusion:　We　conclude　that　combination　of　MRI　and　MRS　characteristics　can　provide　significant　indicators　for　ischemic　damage　at　different　stage　of　cerebral　ischemia　in　a　rat　model.