Sinhala (සිංහල, ISO 15919: siṁhala, pronounced [ˈsiŋɦələ]), also known as Sinhalese (older spelling: Singhalese) in English, also known locally as Helabasa, is the mother tongue of the Sinhalese people, who make up the largest ethnic group in Sri Lanka, numbering about 15 million. Sinhala is also spoken, as a second language by other ethnic groups in Sri Lanka, totalling about 3 million. It belongs to the Indo-Aryan branch of the Indo-European languages. Sinhala is one of the official and national languages of Sri Lanka, along with Tamil. Sinhala, along with Pali, played a major role in the development of Theravada Buddhist literature.

Sinhala has its own writing system, the Sinhala alphabet, which is a member of the Brahmic family of scripts, and a descendant of the ancient Indian Brahmi script.

The oldest Sinhala inscriptions found are from the 6th century BCE, on pottery; the oldest existing literary works date from the 9th century CE.

The closest relative of Sinhala is the language of the Maldives and Minicoy Island (India), Dhivehi.