Computational　fluid　dynamics　(CFD)　is　a　numerical　method　for　modeling　hemodynamics,　which　has　been　applied　to　the　study　of　internal　carotid　artery　aneurysm.　And　the　lattice　Boltzmann　model　has　received　considerable　interest　as　an　efficient　method　of　computing　a　variety　of　fluid　flows,　especially　with　complex　geometrical　configurations.　Therefore,　3-dimensional　mathematical　model　of　interal　carotid　artery　vessels　with　aneurysm　based　on　CTA　were　created.　Furthermore,　CFD　calculations　were　performed　by　using　lattice　BGK　model　with　the　assumption　of　Newtonian　fluid　property　for　blood　and　the　rigid　wall　property　for　the　vessel　and　the　aneurysm.　The　results　suggest　that　the　lattice　BGK　model　has　the　potential　to　be　a　useful　clinical　tool　for　the　prediction　of　the　hemodynamics　in　internal　carotid　artery　aneurysm.　And　the　geometric　configuration　of　aneurysm　is　essential　to　the　hemodynamics　in　aneurysm.　©2009　IEEE.