Abstract: With the advent of the large-scale decommissioning period of photovoltaic modules, their resource treatment has become key to promoting the green development of the photovoltaic industry throughout its entire life cycle. To achieve efficient recovery of high-value materials such as aluminum, silver, and silicon, this study proposes a combined process of “thermal treatment + three-stage wet stepwise leaching”. Retired crystalline silicon cells were mechanically crushed and thermally treated at 800 ℃, followed by a three-stage leaching process: primary leaching with hydrochloric acid/sulfuric acid to dissolve aluminum, secondary leaching with nitric acid to extract silver, and tertiary leaching with hydrofluoric acid to remove the Si₃N₄ anti-reflection layer and purify silicon. The study systematically investigated the effects of parameters such as acid type, concentration, reaction time, liquid-solid ratio, and temperature on the leaching behavior at each stage. The results showed that under the conditions of HCl with mass fraction 10%, a liquid-solid ratio of 5∶1 mL/g, 50 ℃, and 30 min, the primary leaching achieved an aluminum leaching rate exceeding 80%, with a silver leaching rate below 3%, demonstrating good selectivity for aluminum. Increasing the HCl concentration or using H₂SO₄ with mass fraction 60% could increase the aluminum leaching rate to over 94%, but silver dissolution significantly increased, and the high concentration of sulfuric acid easily caused operational issues. In the secondary leaching, low-concentration nitric acid （mass fraction 15%） showed relatively high silver leaching performance due to reduced aluminum surface passivation; increasing the liquid-solid ratio to 8∶1 mL/g promoted silver dissolution, while raising the temperature to 70 ℃ decreased the leaching rate due to nitric acid volatilization. In the tertiary leaching, under the conditions of HF with mass fraction 5%, 25 ℃, 50 min, and a liquid-solid ratio of 5∶1 mL/g, the anti-reflection layer was effectively removed, yielding silicon powder with a purity exceeding 60%; the HF system was sensitive to reaction time and temperature, with lower temperatures favoring reduced volatilization and extended reaction time significantly increasing silicon content. This stepwise leaching process fully utilizes the differences in reactivity of aluminum, silver, and Si₃N₄ in different acid media, achieving sequential separation and enrichment of multiple components, significantly improving reagent utilization efficiency, and reducing the consumption of strong acids and waste liquid discharge. Compared to direct single-step wet processing, this process demonstrates clear advantages in aluminum/silver selectivity, silicon recovery purity, and environmental friendliness, providing a reliable technical pathway for the high-value recycling and industrial application of decommissioned crystalline silicon photovoltaic modules.