As for the magnesium-lithium (Mg-Li) alloys for the applications of rapid corrosion material, enhancing their mechanical properties while maintaining the degradation rate poses a significant challenge. Simultaneously, it is crucial to elucidate the behavior of the long period stacking ordered (LPSO) phase in the corrosion process of as-rolled Mg-Li alloys. This study prepared the as-rolled Mg-8Li-4Gd-1.5Ni alloy with rolling reductions of 30 %, 50 %, 70 %, and 90 % at room temperature. Results indicate that, during the rolling process, the reticular LPSO gradually transitions to a fibrous LPSO and the GdNi3 particles are refined. Additionally, the amounts of twin increases. The alloy with 30 % reduction exhibits the highest corrosion rate, with a weight loss rate of 0.50 mg·cm−2·min−1 in a solute of 3 % KCl. The tensile strength reaches a maximum of 247 MPa. The increase in tensile strength is achieved at the expense of plasticity. The bending of the LPSO phase, the fracture of the secondary phases, and the increase in dislocations and twins increase the chemical reactivity of the alloy, leading to a higher corrosion rate. Rolling brings about the increase in dislocation density, dislocation entanglement, and the reduction in grain size, which indicate that the strengthening mechanisms of the alloy after rolling include work hardening and grain refinement strengthening.