Objectlve To analysis the changes of white matter fiber in autistic disorder.Methods Diffusion tensor imaging(DTI)data were obtained from 18 autistic children and 10 age-,sex-and intelligent quotient matched normal controls.Voxel-based analysis Was applied to assess the fractional anisotropy(FA)in cerebral tissues.Results Compared with the controls,the FA values in autistic children were significantly decreased in the white matter of right inferior frontal gyrus,left middle frontal gyrus and right inferior temporal gyms,and increased in the white matter of left superior parietal lobule(P＜0.001).Furthermore.the white matter changes on left middie frontal gyrus were significandy correlated with the scores of Childhond Autism Rming Scale(CARS)in autistic children(r=-0.63,P=0.005).Conclusion The white matter integrity is probably disconnected in many brain regions in children with autistic disorder.