Abstract: The mechanisms and predictive modeling of solute transport in fractured rocks represent a frontier and hotspot in the fields of hydraulic rock mechanics and hydrogeology. They also address critical scientific challenges, including pollution remediation in fractured bedrock aquifers, safe disposal of high-level radioactive waste, efficient underground resource extraction, leakage tracing and interpretation of chemical signals associated with geohazards. The solute transport processes under various geometric characteristics of fracture network, is simulated, and the quantitative control mechanisms of fracture density, fracture discreteness and mean fracture aperture on solute transport are analyzed. The results indicate that the fracture density and mean aperture are the decisive factors in controlling solute transport, while the influences of the fracture distribution discreteness depends on the connectivity of pathways formed by specific fracture networks. Based on these findings, the parameterization formulas for key transport coefficients, hydrodynamic dispersion coefficient (D) and solute transport velocity (V_t), are developed using the dimensionless fracture density and mean aperture. These formulas are incorporated into the classical macroscopic advection–dispersion analytical solution to establish predictive model for solute transport processes based on the geometric parameters of fracture network. A comparison with the numerical results under various conditions validates the model's accuracy and reliability. The proposed model enables high-fidelity prediction of solute transport processes using only the geometric parameters of fracture network and hydrodynamic conditions. This provides critical support for low-cost, efficient predictions of solute transport in fractured rocks. The findings have significant theoretical implications for rapid assessments of subsurface pollution and efficient underground resource exploitation. Additionally, the revealed quantitative control mechanisms of fracture network geometry on solute transport establish a theoretical basis for studying the coupling between the structural evolution of rock mass and the hydrochemical signals. These insights hold potential applications in tracing rock failure states and early warning of geohazards using the hydrochemical signals.