Leclair occupies an important place in the development of violin music in France. His skill as a dancer took him from his native Lyons to Italy, where he may have received violin lessons from Somis before returning to France to settle in Paris. There he entered the royal service in 1733, resigning four years later. Subsequent patrons included Anne, Princess of Orange and the Duke of Gramont, a former pupil. He was murdered in 1764 perhaps by his nephew, also a violinist.

Instrumental Music
Although he also wrote music for the theatre – including, in 1746, the opera Scylla et Glaucus – Leclair is chiefly known for his violin music and in particular for his first two published sets of violin sonatas. The first set of 12, published in 1723, includes two for flute and basso continuo, and the second dozen includes five for flute as a possible alternative to the violin.