Background: Very few studies have investigated the changes in white mater, corpus callosum (CC) specifically, in attention-deficit/hyperactivity disorder (ADHD) patients and its relation to cognitive and behavioral changes in ADHD patients. This study aimed to investigate the correlation between tractography of CC, behavioral and cognitive changes in ADHD patients. Objectives: To detect any morphological changes in corpus callosum in patients with attention-deficit/hyperactivity disorder through diffusion tensor image (tractography) and to elucidate its relation with cognitive and behavioral changes of patients with ADHD. Patients and Methods: A case-control study was done on 100 children divided into two groups; cases and controls at Menoufia University Hospitals. They were selected according to certain inclusion and exclusion criteria. Diffusion tensor imaging (DTI) of CC was done to both groups. Both behavioral and cognitive functions were assessed in correlation with radiological data. Results: There were no significant differences between the groups regarding demographic data that included age and sex, while statistically significant difference (p value <0.001*) was detected in IQ in ADHD (mean IQ was 89.62) compared to control (mean IQ: 96.08). The mean FA value (a measure of white matter consistency in DTI) was higher in control group than in ADHD group in all subdivisions of corpus callosum with no significant difference between the two groups except for the isthmus part (p value 0.034) whose fibers  were originating from sensory motor cortex denoting defective functioning in mentioned areas. Conclusion: Diffusion tensor image study of corpus callosum in attention deficit hyperactivity disorder reflected defective inter-hemispheric connectivity mainly sensory motor cortices through isthmus part of corpus callosum.