Abstract: This paper proposes a real-time control system for traffic lights at a single intersection using fuzzy control. The system uses a PLC as the core of the intelligent traffic controller, and its programming is simple, flexible, and highly reliable. Practical application shows that the fuzzy controller designed in this system can effectively reduce the average vehicle delay at a single intersection, thus providing a new approach to realizing intelligent control of traffic systems . Keywords : PLC; fuzzy control; average vehicle delay 1. Introduction Urban traffic systems are complex systems with randomness, fuzziness, and uncertainty. It is very difficult to establish a mathematical model to reflect the actual traffic conditions at a single intersection. Using fuzzy control methods to design traffic light control systems allows for the establishment of accurate mathematical models, reducing intersection delays and the number of stops, and more precisely controlling nonlinear and random traffic flow at intersections, thus significantly improving intersection capacity. This paper applies a fuzzy control method for vehicle waiting lengths to traffic lights at a single intersection, utilizing a programmable logic controller (PLC), a mature technology in industrial applications. For details, please click: Fuzzy Control of Intersection Traffic Lights Based on PLC