<p>Antibiotic pollution has been widely present in different water environments, especially in river and lake water bodies, posing a potential threat to human health and ecosystem. However, their transport behaviors under river and lake background remain largely unknown. In this study, the effects of the river sediment particles (RSPs) on the transport of ciprofloxacin (CIP) in saturated porous media were investigated. Batch adsorption experimental results showed that the Langmuir model can better describe the adsorption process of CIP on RSPs, and the maximum adsorption capacity (<i>q</i>_<i>max</i>) of CIP onto RSPs was 26.75&#xa0;mg/g. Column experiment results showed that RSPs significantly inhibited the transport ability of CIP. Due to the slow desorption process, there was a prolonged elution for CIP. Collision theory and particle size analysis showed that mechanical straining, gravity sedimentation were the important retention mechanisms. Combined with the characterization analyses of the RSPs parameters and FTIR&#xa0;spectra, the electrostatic interaction, hydrophobic binding, ion exchange, cation-bridging, complexation, and hydrogen bonding were the main adsorption mechanisms. The two-site nonequilibrium transport model and two kinetic site attachment-detachment model were used to simulate the transport of CIP and RSPs, respectively. These findings help quantitatively predict the transport behavior of antibiotics in natural water environment and better assess the ecological risk of antibiotics.</p>