In the past decade, the use of bimetallic nanoparticles (NPs) as catalytic systems has demonstrated to be an effective method to overcome the unfortunate shortage of expensive Pd-like metals. These NP systems exbibit excellent catalytic activities. In this paper, we present a method to immobilize PdRu and CuRu NPs in the mesopores of hierarchical porous SiO2 using a supercritical CO2 (scCO2) solution, employing commonly available metal-organic complexes as feed materials. Scanning TEM coupled with electron dispersive X-ray spectroscopy (STEM-EDX) revealed the homogeneous distribution of the single metal components in the NPs. The resulting PdRu@SiO2 and CuRu@SiO2 systems exhibited higher activities for CO oxidation than those of monometallic Pd@SiO2, Ru@SiO2, and Rh@SiO2. Our results show that coupling Ru with Pd or Cu in nanosized structures can afford excellent catalytic systems at a lower cost compared to that of their monometallic counterparts.