L series

L series may refer to:
 * L-series trains in China
 * Saturn L series – sedans and station wagons
 * L-function
 * Honda L engine
 * Nissan L engine
 * Dirichlet L-function - mathematical functions in number theory
 * Rover L-series engine
 * Ford L series – trucks
 * Canon L lens
 * International Harvester L series – trucks
 * Lincoln L series – 1920 luxury cars
 * Cummins L-series engine
 * ThinkPad L series – laptop computers
 * Mercedes-Benz L-series truck
 * Rolls-Royce–Bentley L-series V8 engine
 * Sony Vaio L series – desktop computers
 * Subaru Leone
 * System Sensor L-Series fire alarm notification appliances
 * Artin L-function
 * QI (L series), the twelfth series of quiz show QI
 * L-Series, a pejorative term for Indian company T-Series