Objective       To explore the application of blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) in differentiation between glioma and encephalitis by comparing the changes of amplitude of lowfrequency fluctuation (ALFF) in the patients with glioma or encephalitis and the healthy volunteers. Methods       Sixty patients

including 30 diagnosed with glioma and 30 diagnosed with encephalitis

and 40 healthy controls were enrolled for this prospective casecontrol study. All patients underwent resting-state BOLD-fMRI examination on both ipsilateral lesion and contralateral normal brain areas

and the healthy Volunteers underwent the examination too. Their ALFF values were processed and calculated by DPARSF software. Then the subjects were further divided into 6 groups

i.e.

ipsilateral glioma group (IGG)

contralateral glioma group (CGG)

ipsilateral encephalitis group (IEG)

contralateral encephalitis group (CEG)

corresponding areas of glioma in healthy control group (CAGHCG) and corresponding areas of encephalitis in healthy control group (CAEHCG). Independent Sample t-test and paired sample t-test were performed to statistically analyze the changes of ALFF in the patients with glioma and encephalitis compared with healthy controls using SPSS statistics 17.0 statistical software.Statistical significance of ALFF for the diagnosis of glioma or encephalitis was examined by using receiver operating characteristic (ROC) curve.  Results     ①The ALFF differences between groups of IGG and CGG

IGG and CAGHCG

IGG and IEG

（IGG-CGG) /IGG and (IEG-CEG) /IEG were statistically significant (P0.01). ②The ROC analysis showed high values of the area under the curve (AUC)

diagnostic threshold

sensitivity and specificity between groups of IGG and CGG

IGG and IEG. Conclusion       BOLD-fMRI measured ALFF in the glioma  patients  is significantly lower than those of encephalitis

which suggests potential value of ALFF for the differential diagnosis between glioma and encephalitis.