The preparation cost of high-purity hydrogen is high, and the development and utilization of low-cost industrial by-product hydrogen as an alternative gas source is considered an effective way to significantly reduce hydrogen storage costs. Industrial by-product hydrogen typically contains components such as H2S and CO, but the poisoning mechanisms of these gases on the superlattice hydrogen storage alloy during hydrogen absorption and desorption are not well understood. This study systematically investigates the poisoning effects and regeneration behavior of La0.65Mg1.32Ca1.03Ni9Y0.17 superlattice hydrogen storage alloy in 10-3 H2S and CO atmospheres. The experiment adopts a 10 poisoning cycles+1 regeneration mode, with a total of 20 poisoning cycles and 2 pure hydrogen regenerations. The results show that the hydrogen storage capacity of this alloy gradually decreases after 22 cycles in pure hydrogen, but it can be effectively restored after dehydrogenation at 473 K. In the presence of impurity gases, the hydrogen storage capacity retention rates after 10 poisoning cycles with H2S and CO are 3.56% and 2.71%, respectively; after 20 cycles, these values decrease to 3.68% and 1.73%, respectively. After dehydrogenation at 473 K, the retention rates are restored to 40.35% and 98.27%. This indicates that the severity of poisoning by impurity gases follows the order: CO>H2S, while the difficulty of regeneration follows the order: H2S>CO. X-ray diffraction analysis shows that after poisoning, the main phase of the alloy changes from AB3 to AB3H, but it recovers after high-temperature dehydrogenation. X-ray photoelectron spectroscopy results show that after poisoning by H2S, CaS and CaSO4 are formed on the surface of the hydrogen storage alloy, indicating irreversible chemical adsorption. In contrast, after poisoning by CO, no new substances are formed on the alloy surface, indicating that the poisoning effect is due to reversible adsorption. This study clarifies the differentiated poisoning mechanisms of various impurity gases and provides theoretical support for the application of rare-earth superlattice hydrogen storage alloys in complex atmospheres.