Determining the rheological behaviors of the materials in paste technology is very important when transporting the paste. The flow properties of the paste material inside the pipe should be determined when pumping at long distances. In this study, the flow behavior of paste tailings, which consists of different pulp densities (pd), were studied to determine the effect of the particle size distribution of the tailings on surface paste disposal. In other words, the study examined the effect of the particle size distribution on the rheological behavior of the tailings. According to the study's results, tailings with a particle size smaller than 38 mu m behaved like a paste up to 70% pd. However, it lost its paste properties when the pd value increased. In the original tailings sample (as-received), half of the particles were under 38 mu m, the behavior of the paste materials was observed up to 80% pd. In addition, in order to be pumped the paste, it was determined that the amount of < 38 mu m tailings content in the material had to be 20%. Furthermore, the methods are presented in this study for control the effect of the change in particle size distribution on the pumpability of the paste material.