Prionosciadium lilacinum is a plant species native to the Mexican States of Jalisco and Nayarit.

It is common along sunlit roadsides and other disturbed habitats in the region.

[1] Prionosciadium lilacinum is an herb up to 4 m (13 feet) tall.

Flower are light purple, borne in umbels on the ends of branches.

Fruits are ovoid, up to 9 mm (0.35 inches) long.