T series or T-series may refer to:

• Bentley T-series, automobile brand, 1960s to 1980
• Canon T series, camera models, 1980s
• Chevrolet Kodiak, automobile known as the Chevrolet T-Series
• Juniper T-Series, router
• Mazda Titan, automobile known as the Mazda T Series
• Rover T-Series engine, produced in 1990s
• Suzuki T series, motorcycle models manufactured from 1963 through 1977
• T-Series music label of India owned by Super Cassettes Industries
• SPARC T-Series a range of multi-core microprocessors made originally by Sun and now Oracle.
• ThinkPad T Series laptop computers, produced by Lenovo
• T-series (Toronto subway car), built in 1990s

T-Series is a music label owned by the Indian music company, Super Cassettes Industries Private Limited (SCIL). It is also a film production and distribution company. The company later ventured into other consumer products, such as manufacturing incense sticks (Rajni Industries) and manufacturing washing powder (Gopal Soap Industries).