The leaves of Sterculia alexandri are digitate, the leaflets from three to seven in number, although often five.

S. murex, a related species of the genus growing in the Lowveld, far to the north of this tree’s Eastern Cape distribution, also has digitate leaves. The other South African Sterculia species have simple, lobed leaves.

The leaflets of S. alexandri are oblong, rounded to tapering, sometimes with mucronate tips or notched and tapering to the base. The leaflets are dark green and shiny above, pale grey-green below. Leaf texture is leathery. The prominent leaflet midribs are cream coloured, as is the sturdy petiole that may become 10 cm long. Leaflet dimensions reach 10 cm by 2,5 cm, although often only a little over half that (Coates Palgrave, 2002).