Objective To explore the diagnostic value of DWI and MRS for assessment of virus encephalitis versus low-grade glioma. Methods Nineteen patients with virus encephalitis and 20 patients with low-grade glioma were enrolled in this retrospective study. All the study subjects were performed conventional MRI scanning, DWI and MRS sequences. Patients with virus encephalitis were confirmed by clinical biochemical examination and following up, and patients with low-grade glioma were confirmed by histopathology. The values of apparent diffuse coefficient (ADC), Cho/Cr, NAA/Cr and Cho/NAA were measured and compared between virus encephalitis and low-grade glioma group. Results ADC value of virus encephalitis and low-grade glioma group was (1.471±0.032)×10-3mm2 /s and (1.079±0.201)×10-3mm2 /s (P<0.01), respectively. Value of Cho/Cr was (2.442±0.648) and (3.992±0.965)(P<0.01), respectively. Value of Cho/NAA was (3.623±1.221) and (6.585±2.52)(P<0.01), respectively. Value of NAA/ Cr was (2.088±0.484) and (1.292±0.465)(P<0.01). Conclusion There was important clinical value for differential diagnosis of virus encephalitis and low-grade glioma by DWI and MRS, which would play an important role in complementing conventional MRI scan sequences.