Hydraulic conductivity (<i>K</i>) is one of the significant soil characteristics in terms of flow movement and solute transport. It has been recognized that <i>K</i> is statistically related to the grain-size distribution. Numerous models have been developed to reveal the relationship between <i>K</i> and the grain-size distribution of soil, but most of these are inappropriate for fine-grained media. Therefore, a new empirical model for estimating <i>K</i> of low permeability media was proposed in this study. In total, the values of <i>K</i> of 30 soil samples collected in the Jiangning District of Nanjing were measured using the single-ring infiltrometer method. The new model was developed using the percentages of sand, silt and clay-sized particles, and the first and the second rank moment of the grain-size through the moment method as predictor variables. Multivariate nonlinear regression analysis yielded a coefficient of determination (<i>R</i>²) of 0.75, indicating that this empirical model seems to provide a new approach for the indirect determination of hydraulic conductivity of low permeability media.