Upon oxidation, a graphyne-like porous carbon-rich network (GYLPC), which is a two-dimensional carbon material consisting of sp- and sp2-hybridized carbon atoms synthesized via alkyne metathesis reactions, yielded GYLPC oxide (GYLPCO). The highly electron-rich conjugated structure provides this new material GYLPC and its oxide GYLPCO with low reduction potentials, which are found to be able to serve as reductants and stabilizers for electroless deposition of well-dispersed Pd metal nanoparticles. The unique Pd/GYLPCO showed extremely high catalytic activity for a broad scope of nitrobenzene reduction reactions with short reaction time and good yields, even in aqueous media under aerobic conditions. We expect that our approach will further boost research on the design and application of graphyne-like functional materials for catalysis.