In this paper, the yield stress and consistency of cement-ground limestone pastes were measured by RHEOLAB QC rotational viscometer. The relationship between particle size distribution, packing density and rheological properties was studied.The results show that the addition of ground limestone into cement paste make the particle distribution wider and improve the state of particle accumulation.The linear correlation between particle size distribution coefficient n and yield stress and consistency is not high, the correlation coefficient is only 0.60061 and 0.69962 . The correlation coefficient between the packing density and the yield stress and consistency is 0.83058 and 0.84654 respectively, and the correlation between the packing density and the rheological property is higher than that of the particle size distribution coefficient n.The relationship between water film thickness and rheological properties cannot be described by linear function for all cement-ground limestone pastes, among which the yield stress and consistency of the cement paste with 411 m2/kg ground limestone are decreased and the water film thickness is increased.The yield stress and consistency of the cement paste with 807 m2/kg and 1007 m2/kg ground limestone decreased, the water film thickness increased and then decreased, and the yield stress, consistency and water film thickness decrease simultaneously.