The simple leaves of Hermannia cristata are alternate and sessile, here subtending flowers.
The leaf-shape is elliptic or lanceolate to nearly linear. Leaf dimensions are quite variable, from 20 mm to 65 mm in length and 3 mm to 20 mm in width. The margins are toothed.
The hairy blades are uneven, bulging between lateral veins and some net-veining sunken on the upper surfaces (Manning, 2009; Pooley, 1998; Germishuizen and Fabian, 1982; iNaturalist).