Ficus ingens leaves are spirally arranged and close together near stem tips where they sprout annually in spring after a short leafless rest for the tree.
The (variable) leaf shape is ovate to elliptic or oblong-lanceolate. The leaf tip tapers to an acute point, tapers broadly or is almost rounded; the base is rounded, square to slightly lobed or heart-shaped. Leaf size varies between 6 cm to 15 cm in length and 3 cm to 10 cm in width. The leaf margins are entire.
The leaf midrib and lateral venation, pale yellow or cream-coloured, are prominent on the lower leaf surface, slightly recessed above. The five to eight lateral veins on either side of the midrib ascend parallel towards the margins without reaching it, curving inwards to join the next vein. The lowest pair of lateral veins branch into the basal leaf lobes.
The colour of the mature leaf, between the initial glossy red and eventual coppery or bronze phases, is freshly bright green to olive green. Leaf texture is thin and brittle.
Leaf petioles are slender, about 1 cm in length; occasionally longer than 4 cm (Coates Palgrave, 2002; Pooley, 1993).