Series 4 could refer to:
Aston Martin Lagonda Series 4, the automobile model BMW 4 Series, the automobile model line GeForce 4 series, line of nVidia video cards Scania 4-series, the truck model line South African Class 6E1, Series 4, electric locomotive series Series 4, the registered options principal exam
See also 400 series (disambiguation) System 4 (disambiguation)