YNi2B2C intermetallic superconductor has the fluctuation magnetoconductance showing the 3D scaling behavior. In the mixed state, due to this fluctuation effect, the vortices form a solid phase at low temperature and make a liquid phase near T-c similar to high-T-c materials. Moreover, the Vortex solid becomes a lattice at low fields and the vortex glass transition is found for high fields of H greater than or equal to 2 T while the liquid phase is narrow. (C) 1999 Elsevier Science B.V. All rights reserved.