Using green, environmentally friendly and resource-rich cellulose as a raw material, a ligand-free and highly dispersed palladium (Pd) nano-catalyst was successfully prepared in a facile way. A variety of characterization results showed that the Pd nanoparticles (NPs) were uniformly spread on the cellulose nanoporous microspheres, with an average particle size of ∼2.75 nm. As a carrier, cellulose microspheres with nanoporous structure and rich –OH groups greatly promoted the attachment and distribution of the highly dispersed Pd NPs, along with the diffusion and exchange of reactants, so as to greatly promote the catalytic activity. In the Suzuki–Miyaura coupling reaction, the catalyst of C–Pd exhibited excellent catalytic activity (TOF up to 2126 h⁻¹), broad applicability, and good recyclability with almost no active loss in 6 continuous runs. This utilizing of bioresources to build catalyst materials is important for sustainable chemistry.