Purpose <p>To immobilize snailase on SBA-15 to enhance the efficient conversion of <i>Epimedium wushanense</i> extracts for the preparation of rhamnosyl icariside II.</p> Methods <p>The snailase was covalently coupled to amino and aldehyde modified SBA-15, and the immobilization conditions were optimized. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), N₂ adsorption-desorption analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the physicochemical properties of immobilized snailase. The optimal enzymatic hydrolysis conditions, enzymatic kinetic parameters, storage stability and reusability of the immobilized snailase were investigated.</p> Results <p>The optimal immobilization conditions were pH 5.0, temperature 30℃, immobilization time 3&#xa0;h and snailase concentration 10&#xa0;mg⋅mL^− 1. The immobilized snailase showed a retained activity of 235.8 µmol⋅(h⋅g)⁻¹ and a high enzyme loading capacity of 249.6 mg⋅g^− 1 support. The optimum hydrolysis conditions for immobilized snailase were pH 5.5, temperature 50℃, substrate concentration 3.0&#xa0;mg⋅mL^− 1, and reaction time 6&#xa0;h. The <i>V</i>_max and <i>K</i>_m of the immobilized snailase were 3.92&#xa0;µg⋅min^− 1 and 1.18 mmol⋅L^− 1, respectively.</p> Conclusion <p>The immobilized snailase has a high enzyme loading capacity, strong conversion capability, better storage stability and good reusability, making it suitable for the efficient conversion of <i>Epimedium wushanense</i> extracts to produce rhamnosyl icariside II.</p>