Abstract: Objective To evaluate the predicting value of the marker of endothelial injury: plasma matrix metalloproteinase-9( MMP-9) and high sensitivity C-reactive protein( hsCRP) level on the progression of acute anterior circulating territory infarction progressing to malignant middle cerebral artery infarction (m-MCAI). Methods 90 patients with acute anterior circulating territory infarction, in which 46 patients progressed to m-MCAI, were collected and sampled consecutively. The plasma MMP-9 and hsCRP of all patients were determined by ELISA and immunotur-bidimetry,respectively,at admission. And the clinical characters and cranial CT features of the patients were analyzed. Results At admission,the plasma MMP-9 level in the patients with m-MCAI(242.0 ±58.0)ng/ml was significantly higher than that in the patients with non m-MCAI( 169.0 ± 50.0) ng/ml( P < 0. 01) ,the plasma hsCRP level in the patients with m-MCAI(6.25 ±1.2) ng/ml was significantly higher than that in the patients with non m-MCAI( 1.55 ± 0.9) mg/ml( P <0. 01).Conclusion The increased level of plasma MMP-9 and hsCRP could be predictors for the m-MCAI proceeding.