This study explored the interactions between different polyolefins using a commercial Ru/C catalyst-mediated hydrogenolysis of polypropylene (PP), low-density polyethylene (LDPE), and their mixtures. The effects of the mass ratio of polyolefins to the catalyst, temperature, pressure and time on the yield of products and the internal components of liquid alkane products were studied, and the optimum conditions for solo plastic hydrogenolysis were determined. The highest liquid alkane yields of PP (46.70 %) and LDPE (70.70 %) were obtained at 250 and 210 °C, respectively. Further, the interactions between PP and LDPE during co-hydrogenolysis were observed. The temperature had a significant influence on the gaseous and liquid products, and we proposed a two-step hydrogenolysis reaction process for a mixture of polyethylene with polypropylene conducted at various temperatures. Co-hydrogenolysis provides a high-value utilization path for polyolefins that are difficult to separate during recovery.