Ti-based bulk metallic glasses (Ti40Zr25Cu9Ni8Be18 )100-xNbx with x=0 to 5at.% are prepared by copper-mold casting. The glass formation ability is almost unchanged by addition of Nb. The compression plasticity is,however, apparently changed, from 3% at x=0 to 13% at x=3, about 330% increases at the strain rate of 1×10-4s-1. The increment of the plasticity can be attributed to the segregation of Nb in the area of shear bands during the compression processing. An effective way to increase the plasticity of Ti-based bulk metallic glasses is thus proposed.