The hydrogenation of levulinic acid (LA) is an important route to prepare high-value biomass-based platform compound γ-valerolactone (GVL). Herein, a highly efficient RuIr alloy bimetallic catalyst supported on SiC for the aqueous hydrogenation of levulinic acid (LA) into γ-valerolactone (GVL) under mild conditions. The RuIr/SiC catalyst exhibited a high LA conversion and GVL selectivity (both >99%) in water under 0.2 MPa H2 pressure at 25 oC. The excellent performance is due to the synergistic effect of Ru and Ir nanoparticles on the semiconducting SiC. Moreover, the activity of RuIr/SiC alloy catalyst did not change significantly after 5 cycles, indicating that the bimetallic alloy catalyst has high stability.