Objective:　To　investigate　the　impact　of　stent　porosity　on　hemodynamics　in　the　simulated　sigmoid　sinus　diverticulum.　Methods:　An　idealized　hemodynamic　model　of　sigmoid　sinus　diverticulum　(S0　model,　no　stent)　was　constructed　based　on　computational　fluid　dynamics　(CFD).　The　hemodynamic　changes　in　models　stented　with　different　porosities　of　75%,　50%　and　25%　(corresponding　to　S1,　S2,　S3　model)　were　observed.　Results:　The　mean　flow　velocities　in　sigmoid　sinus　diverticulum　of　model　S0,　S1,　S2　and　S3　was　12.65,　4.68,　2.20　and　0.41　mm/s,　respectively.　Compared　with　model　S0,　the　velocities　in　model　S1,　S2　and　S3　decreased　by　63.00%(7.97/12.65),　82.61%(10.45/12.65)　and　96.76%(12.24/12.65),　respectively.　The　area　of　high　pressure　and　high　wall　shear　stress　(WSS)　in　diverticulum　distal　wall　reduced　gradually　with　the　decrease　of　stent　porosity.　Meanwhile,　the　pressure　and　WSS　tended　to　distribute　uniformly　in　the　entire　diverticulum.　However,　the　mean　pressures　for　model　S0,　S1,　S2　and　S3　in　diverticulum　(64.04,　63.86,　62.54　and　60.95　Pa,　respectively)　showed　no　significant　change.　Conclusion:　Stent　with　lower　porosity　can　significantly　improve　blood　flow　and　hemodynamic　stress　conditions　in　the　simulated　sigmoid　sinus　diverticulum.　Copyright　©2019　by　the　Press　of　Chinese　Journal　of　Medical　Imaging　and　Technology.