Abstract With the worsening of plastic pollution and increasing attention being paid to sustainable development, the upgrading and recycling of waste plastics have become important tasks. In this study, organic ligand‐modified PdPr nanosheets (PdPr O‐NSs) with the lanthanide contraction effect are constructed and used as high‐performance electrocatalysts for the value‐added transformation of polyethylene terephthalate. PdPr O‐NSs only require a potential of 0.75 V to supply current densities of 200 mA cm −2 . The Faraday efficiency and selectivity for the primary product glycolic acid reached 97.5% and 94.6% at 0.675 V, respectively. Density functional theory calculations confirm that the existence of Pr and n ‐octanoic acid adjusts the electronic structure and coordination environment, improving the electron transfer efficiency and catalytic performance. This work not only provides a new strategy for constructing novel and efficient lanthanide‐doped nanomaterial electrocatalysts but also paves the way for recycling waste plastics.