Abstract: Hydrogen production via the hydrolysis of bulk active aluminum alloys presents distinct advantages, such as low water quality requirements, on-site hydrogen generation, and on-demand supply. This method effectively addresses critical challenges in hydrogen production, storage, transportation and safety, establishing it as a promising candidate for hydrogen supply in fuel cell applications. However, the high cost of gallium (Ga), a key component in active aluminum alloys, remains a major bottleneck restricting its large-scale deployment and application in the hydrogen energy field. Therefore, achieving reduced Ga consumption and efficient recycling represents an essential pathway to promote the development of such materials toward low-cost, eco-friendly and industrial application. Based on E-pH (Pourbaix) diagram analysis of the Al-Ga-Mg-Sn quaternary system, this study systematically investigated the leaching performance in acidic (pH < 2) and alkaline (pH>12) systems for solid residues generated from hydrolytic hydrogen production. Utilizing the differences in dissolution behaviors of Al and Ga between acidic and alkaline environment, an acid/alkali leaching process was developed to realize solid-liquid separation and one-step recovery of elemental Ga. The effects of leaching agent type and concentration, temperature, and solid-to-liquid ratio on Ga recovery efficiency were explored, and solid-to-liquid ratio on Ga recovery efficiency were explored, and the essential differences in Ga recovery mechanisms between acidic and alkaline systems were revealed. The results indicate that in HCl acidic system, Ga is easily oxidized to ionic state and enters the solution, making the recovery of elemental Ga difficult. In contrast, NaOH exhibits superior leaching performance compared to KOH in alkaline systems. A maximum Ga recovery efficiency of 26% is achieved under the conditions of 90 ℃, 0.4 mol/L NaOH, and a solid-to-liquid ratio of 1 g∶40 mL. Increasing the temperature can significantly improve the Ga recovery efficiency. The difference in recovery efficiency between acidic and alkaline systems stems from the distinct corrosion behaviors of the solid residue. HCl induces localized pitting corrosion, resulting in Ga being trapped in the residue pores and difficult to leach out, whereas NaOH promotes uniform corrosion, which facilitates the precipitation and aggregation of Ga. The One-step acid/alkali leaching process enables the on-site recovery of elemental Ga, eliminating the multi-step separation and enrichment procedures involved in conventional "ionic dissolution-secondary conversion" processes and thus greatly simplifying the process flow.