ENI may refer to:

• Eni, the Italian oil and gas corporation ENI S.p.A.
• Escuela Nacional de Inteligencia, an Argentine intelligence academy
• El Nido Airport, an airport in the Philippines with IATA code ENI
• E.N.I., a Croatian pop band
• European Neuroscience Institute, a cooperation of the MPI for Biophysical Chemistry and the Medical School of Göttingen University
• ENI number for ships

Eni S.p.A. is an Italian multinational oil and gas company headquartered in Rome. It has operations in 79 countries, and is currently world's 11th largest industrial company with a market capitalization of 68 billion euros (US$ 90 billion), as of August 14, 2013. The Italian government owns a 30.303% golden share in the company, 3.934% held through the state Treasury and 26.369% held through the Cassa Depositi e Prestiti. Another 2.012% of the shares are held by People's Bank of China. The company is a component of the Euro Stoxx 50 stock market index.