Objective To study the value of DSI Studio combined with diffusion tensor imaging(DTI)in evaluating the prognosis of postoperative motor function in patients with brain functional area tumors.Methods From January 2018 to August 2022,41 patients with brain functional area tumors who underwent surgical treatment and were pathologically diagnosed in our hospital were included in the study.All patients completed 3.0 T MRI routine sequence and DTI examination.DTI parameters of the corticospinal tract(CST)projection area of posterior limb of the internal capsule on the affected side and the healthy side were measured respectively,and the correlation with MRC muscle strength score and the CST grade was analyzed.Results The FA value of the affected side was significantly lower than that of the healthy side(P＜0.001),and the ADC value of the affected side was significantly higher than that of the healthy side(P＜0.001).The FA value of the affected side and the lateral rFA value were negatively correlated with the CST grade(P＜0.01).ADC value and rADC value were positively correlated with CST grade(P＜0.01).The FA value of the affected side and the partial rFA value were positively correlated with the degree of muscle strength score before and after surgery(P＜0.01).ADC value and rADC value were negatively corre-lated with CST grade(P＜0.01).Preoperative CST grading was negatively correlated with contralateral muscle strength.The area under the ROC curve of FA value,rFA value,ADC value,rADC value,and CST grade were 0.820(P＜0.01),0.796(P＜0.01),0.698(P＜0.05),0.638(P＞0.05)and 0.708(P＜0.05),respectively.Conclusion DTI parameters,muscle strength score and CST grade have certain value in the evaluation of postoperative motor function prognosis in patients with brain functional tumors.