Abstract: OBJECTIVE To investigate the relationship between the expression of endocannabinoid metabolic enzyme monoacylglycerol lipase (MAGL) in human brain glioma tissues and the grade of brain glioma, explore its clinicopathological significance. METHODS twenty-three patients with brain glioma, including one case with WHO grade Ⅰ, 7 cases with WHO grade Ⅱ, 5 cases with WHO grade Ⅲ, and 10 cases with WHO grade Ⅳ, performing surgical excision were enrolled in the study and 8 samples of normal brain tissues from patients performing decompression operation due to cerebral hernia served as controls. qRT-PCR and LC-MS were used to detect the mRNA and activity of MAGL. RESULTS The mRNA expression and activity of MAGL was significantly higher in low grade (WHO grade Ⅰ-Ⅱ) and high grade (WHO grade Ⅲ-Ⅳ) brain glioma tissues than those in the normal brain tissues, and both were negatively correlated to the pathological grade (P<0.01). the MAGL mRNA expression was positively correlated with the the MAGL activity. CONCLUSION MAGL may be involved in the occurrence and development of brain glioma. Detection of MAGL expression may be can evaluate the matignant of brain gliomas.