Objective To study the correlation between MR diffusion weighted imaging (DWI) and pathologic features of disseminated cortical inhibition in astrocytoma. Methods Used retrospective study method, From September 2012 to February 2016 in our hospital, 84 cases with surgically and pathologically proved astrocytoma patients were selected for treatment that included pathological classification for low grade astrocytoma in 30 cases (10 cases of WHO grade Ⅰ, 20 cases of WHO grade Ⅱ), pathological classification for high-grade astrocytoma in 54 cases (44 cases of WHO grade Ⅲ, 10 cases of who grade Ⅳ). All cases were given conventional MRI and spread of cortical inhibition of MR diffusion-weighted imaging (DWI) analysis. Results MRI routine examination display low grade astrocytomas were showed isometric T1 and T2 signal nodules or masses, without peritumoral edema zone, clear boundary and were no obvious space occupying effect; high grade astrocytoma were showed slightly long T1, T2 signal nodules shadow or masses, peritumoral edema with significant and were obvious mass effect, fuzzy boundaries. After judging, MRI for astrocytic tumor pathological diagnosis sensitivity, specific and accuracy were 93.3%, 90.7% and 91.7%. MR DWI spreading cortical depression showed that the tumors and peritumoral ADC and rADC values in the low grade astrocytoma were significantly higher than that of high-grade astrocytomas, the difference were statistically significant (P<0.05). Conclusion Astrocytoma spreading cortical inhibition of MR diffusion weighted imaging can effectively reaction pathologic grade, it able to provide more information about the function of, improve the accuracy of diagnosis is a useful supplement for conventional MRI that has good application values.