Traditionally, waste plastics have been recycled using crude recycling processes, which pose serious environmental pollution and low recycling efficiency. The best option for managing waste plastics is to upgrade them into high‐value‐added chemicals by breaking down specific chemical bonds in plastic polymers. Herein, this article reviews recent representative research advancements in photo‐ and electrodegradation of plastics for obtaining small‐molecule, high‐value‐added chemicals. The focus is on the application and analysis of emerging technological processes and catalytic materials concepts in these upcycling pathways, with particular emphasis on the diverse functions exhibited by various catalysts. Through the optimization of plastic degradation processes with the rational design of degradation technical processes and catalysts, efficient and selective access to the target products, with the assistance of light and electrical energy with similar action principles, can be achieved. These efforts have yielded promising results, paving the way for resourceful plastic recycling. Particularly, the challenges that arise in upcycling of waste plastics are seriously discussed, and reasonable recommendations have been made to understand future developments and prospects in this research area. It is believed that photocatalysis and electrocatalysis, two emerging degradation methods, play an increasingly important role in the field of plastic upcycling.