Class 120 may refer to:
DB Class 120, a class of electric locomotives operated by DB Fernverkehr in Germany. British Rail Class 120, a type of diesel railcar built by Swindon Works for British Rail. Renfe Class 120, a type of electric multiple units used in Spain. OSE Class 120, a class of electric locomotives operated by Hellenic Train. Furness Railway 120 Class, a class of four 4-4-0 steam locomotives. DR Class 120, a Soviet-built diesel locomotive for heavy freight trains.