Objective To explore the utility of apparent diffusion coefficient(ADC)histogram analysis for differentiating genetic subtypes of diffuse lower-grade gliomas. Methods A total of 55 patients with WHO grade Ⅱ/Ⅲ diffuse lower-grade gliomas who underwent preoperative routine brain magnetic resonance imaging and diffusion weighted imaging in our center were retrospectively evaluated.Among whom there were 14 patients with isocitrate dehydrogenase(IDH)wild-type gliomas(IDH wt group),19 patients with IDH-mutant 1p19q intact gliomas(IDH mut 1p19q int group),and 22 patients with IDH-mutant 1p19q co-deleted gliomas(IDH mut 1p19q del group).The whole-lesion ADC values derived from histogram analysis(including ADC mean ,ADC minimum ,ADC5%,ADC10%,ADC25%,ADC50%,ADC75%,ADC90%,ADC95%,ADC maximum ,mode,range,skewness,kurtosis,standard deviation,inhomogeneity,and entrophy)were measured for each patient.All parameters between the different genetic subtypes were compared by using the Student's t test or Mann-Whitney U test.Receiver operating curve(ROC)analysis was used to assess the diagnostic performance of ADC histogram in distinguishing the different genetic subtypes. Results Compared with IDH wt group,the ADC75%( P =0.021),ADC90%( P =0.015),ADC95%( P =0.014),ADC maximum ( P =0.035),range( P =0.009),standard deviation( P =0.001)and inhomogeneity( P =0.001)were significantly lower in IDH mut group;in contrast,the ADC minimum ( P =0.031)and kurtosis( P =0.020)of IDH mut group were significantly higher than those in IDH wt group.The ADC mean ( P =0.010),ADC5%( P =0.016),ADC10%( P =0.012),ADC25%( P =0.007),ADC50%( P =0.005),ADC75%( P =0.015),and mode( P =0.002)were significantly higher in IDH mut 1p19q int group than in IDH mut 1p19q del group.Inhomogeneity achieved the highest area under ROC(AUC)(0.811)in differentiating IDH mut gliomas and IDH wt gliomas,with a cutoff value of 0.229;the sensitivity and specificity were 85.7% and 73.2%.The mode achieved the highest AUC(0.744)in differentiating IDH mut 1p19q int gliomas and IDH mut 1p19q del gliomas,with a cutoff value was 1448.75×10 -6 mm 2 /s;the sensitivity and specificity were 57.9% and 90.9%. Conclusion ADC histograms analysis may be helpful to differentiate genetic subtypes in lower-grade gliomas.