Plants roots are known as an important driving force for the change of soil structure and soil hydraulic parameters (SHP). However, there is a lack of appropriate modelling approaches to root-pore-SHP interactions with quantitative descriptions, which has led to knowledge gaps in the effects of roots on SHP at larger scales. A consequence of this gap is the bias in the simulation and prediction of hydrological processes such as infiltration, runoff and evaporation in catchments. In this paper, available literature is reviewed and used to quantify the changes and effects of plant roots on SHP. In addition, its relationships with plant and soil type are proposed. The quantitative expression of SHP and their prediction models under the dynamic growth of plant roots are summarized. This paper also analyzes problems and future research directions of the quantitative research on root-permeated soils. This study points out that the current research on SHP affecting roots focused on small-scale control experiments, ignoring the interference of soil spatial heterogeneity and environmental factors at large scales. Previous studies found contrasting root effects (on SHP) depending on which processes are dominant, including root growth (or decay) and the density and diameter of roots. Meanwhile, root-induced change of SHP was species (root characteristics), soil type, and time-dependent. Also, related studies indicated that the model’s accuracy and reliability would be improved when considering the temporal dynamics of roots induced by land cover/land use change and seasonal variations in SHP. Few efforts have been undertaken to incorporate root variables into soil function to predict SHP based on roots occupying the soil pore space, changing soil pore size distribution and soil pore network model. Neglecting root-induced change of SHP in hydrologic simulation may lead to high uncertainties. As the root-related dominant process at a larger scale is different to that in small-scale control experiments, there remain significant knowledge gaps that impede the development of quantitative guidance on root-induced change of SHP at a larger scale. It is highlighted that the importance of root effects and associated parameters related to soil structure, and it is becoming a part of hot topic about coupling hydrological and water quality models.