Coal-tar　pitch　was　modified　with　a　bismaleimide　(BMI)　resin.　Rheological　properties　and　carbonization　behavior　of　the　pitch-BMI　resin　composites　and　optical　texture　of　resultant　semi-cokes　were　studied　in　this　paper.　The　carbonization　behavior　was　studied　by　thermogravimetric　analysis　(TGA)　and　Fourier　transform　infrared　(FTIR)　spectroscopy　techniques.　In　addition,　the　optical　texture　of　resultant　semi-cokes　was　characterized　by　polarized-light　microscopy.　Results　show　that　the　BMI　resin　content　has　great　effect　on　the　viscosity　of　the　pitch-BMI　resin　composites.　When　the　BMI　resin　content　is　40　wt.%,　the　rheological　behavior　of　the　pitch-BMI　resin　composite　is　similar　to　that　of　a　thermosetting　resin　with　a　U-type　curve.　Moreover,　the　pitch-BMI　resin　composites　have　better　thermal　stability　than　coal-tar　pitch.　The　addition　of　BMI　resin　results　in　an　increase　in　carbonization　yield　by　6.5%　when　the　BMI　resin　content　is　40　wt.%　of　the　pitch-BMI　resin　composite.　Also,　the　BMI　resin　has　great　effect　on　formation　of　the　optical　textures.　When　the　BMI　resin　content　is　10　wt.%　of　the　pitch-BMI　resin　composite,　the　addition　of　BMI　resin　clearly　improves　the　development　of　anisotropy　on　carbonization　and　the　optical　texture　is　flow　domain　anisotropy.　Furthermore,　there　are　higher　aromaticity　and　more　condensed　polynuclear　structures　in　resultant　semi-cokes　with　increasing　heat　treatment　temperature.　©　2009　Elsevier　B.V.　All　rights　reserved.