Maharaja Ranjit Singh of Punjab (1780–1839) was the founder of the Sikh Empire.
Ranjit Singh may also refer to:
- Ranjit Singh of Bharatpur (1745–1805), Jat ruler of the Bharatpur princely state in Rajasthan, India
- Ranjit Singh (cricketer) or Ranjitsinhji (1872–1933), ruler of the Indian princely state of Nawanagar from 1907 to 1933 and cricketer
- Ranjit Singh (cricketer, born 1994), Indian cricketer
- Ranjit Singh (athlete) (born 1957), Indian Olympic athlete
- Ranjit Singh (volleyball), Indian volleyball player
- Ranjit Singh (How I Met Your Mother character)
- Ranj Singh, British doctor and TV presenter
- Ranjit Singh Lobo, fictional character portrayed by Danny Denzongpa in the 1981 Indian film Bulundi
- Thakur Ranjit Singh, fictional character in the 1973 Indian film Dhund, played by Denzongpa