Dispersion　property　is　an　important　fact　to　generate　white　light.　Different　structures　could　change　the　dispersion　properties　of　fibers.　This　paper　demonstrates　how　the　white　light　was　generated　when　the　ultrashort　pulse　propagated　in　a　tapered　fiber.　We　simulated　how　the　supercontinuum　was　generated　in　a　variety　of　tapered　fibers　which　have　different　parameters.　The　supercontinuum　range　could　be　reached　from　680nm　to　1750nm.　It　is　shown　that　the　width　and　the　shape　of　the　supercontinuum　depend　on　both　the　fiber　parameters　such　as　the　diameter　or　the　length　of　tapered　waist　regime　and　pulse　peak　power.　The　paper　also　discussed　the　influence　of　the　different　dispersion　and　nonlinear　effects　in　detailed,　including　GVD　(Grouped　Velocity　Dispersion),　SPM　(Self　Phase　Modulation),　TOD　(Third　Order　Dispersion),　SS　(Self　Steeping),　and　SRS　(Stimulated　Raman　Scattering).　Through　the　numerical　simulation,　it　presents　when　the　ultrashort　pulse　propagates　in　tapered　fibers　with　anonymous　dispersion,　the　Stimulated　Raman　Scattering　effect　plays　an　important　role　in　the　long　wave　range　of　the　supercontinuum.　The　influence　of　the　higher　order　dispersion,　especially　third　order　dispersion,　on　the　anti-Stokes　part　in　the　supercontinuum　process　was　also　discussed.　A　smoother　and　broader　supercontinuum　could　be　obtained　after　choosing　the　suitable　parameters　of　the　tapered　optical　fibers,　especially　the　diameter　or　the　length　of　tapered　waist　regime.