A mixture system containing particles of different properties always tends to segregation, and such particle properties include differences in particle size, in density, in shape, and in particle resilience. This paper intends to investigate the effect of size ratios of particles on segregation of dry particulate mixtures in a vibration bed. The effect of difference in particle density is also studied in the research. The rise time of a larger disk placed in the background of smaller beads in a vibration bed was measured to characterize the segregation. It shows that the rise time of the disk intruder decreases with the increase of the disk intruder diameter. The similar analysis procedure is also employed to investigate segregation of particles with different densities in a vibrating bed. The influence of vibration conditions on segregation in a vibrating bed is also discussed in the paper.