Lepontic is an extinct Celtic language that was once spoken in Northern Italy between 700 BCE and 400 BCE.

The language is only known from a few inscriptions discovered that were written in a variety of the Northern Italic alphabet , which was related to the Old Italic alphabet. These inscriptions were found in an area centered around Lugano, including Lago di Como and Lago Maggiore. The closely related Rhaetic and Venetic dialects had similar scripts, and many scholars believe that they and the Lepontic writing systems are the direct models adopted for the Germanic runic alphabets.

Some scholars believe that Lepontic may be a dialect of Gaulish. Others, however, question the classification of this dialect as Gaulish and even Celtic, but consider it, together with a number of other dialects of ancient Northern Italy and Southern Gaul, as related to the Ligurian language.

Lepontic was eventually assimilated by Latin, after the Roman Empire gained control over Northern Italy.