Hydrogen permeation is a pivotal factor inducing hydrogen embrittlement (HE) in pipeline steels. Alloying presents an effective strategy for enhancing both the mechanical properties and HE resistance of these steels. In this review, the atomistic regulating mechanisms of alloying elements on critical steps of hydrogen permeation in pipeline steels are systematically summarized. The hydrogen permeation is considered to involve four critical steps: the adsorption and dissociation of hydrogen molecules, the adsorption and permeation of hydrogen atoms on the surface, the dissolution and migration in the bulk phase, and the segregation behavior at defects.The results show that single alloying element doping can effectively inhibit hydrogen permeation by inducing local lattice distortion, changing charge distribution, regulating bonding characteristics or increasing energy barriers. Furthermore, multi?elements synergic-doping and multi-principal element alloy systems exhibit more complex regulation mechanisms,and the synergistic effect of different elements can further enhance the inhibitory effect on hydrogen permeation. Future research can focus on the effect of multi-elements synergic-doping, the optimization and design of high-entropy alloys, hydrogen trapping under environments with complex defect structures and the development of multi-scale simulation methods, aiming to provide theoretical guidance and design strategies for advanced materials resistant to hydrogen embrittlement.