SSgt Jim Penniston (born 1954) was a Staff Sergeant in the 81st Security Police Squadron, United States Air Force, stationed at RAF Bentwaters during the Rendlesham Forest incident of December 1980. He was one of the first responders to the initial reports of unusual lights near the base perimeter.

On the night of December 26 1980, Penniston and Airman First Class John Burroughs were dispatched to investigate. Penniston later reported approaching a triangular craft resting on the forest floor, touching its smooth metallic‑like surface, and observing strange symbols on its side. He documented the encounter in his official notebook, sketching the symbols and noting that the craft emitted a bright light before departing. Penniston’s detailed testimony, supported by his contemporaneous notes, has made him a key primary witness in the Rendlesham case.