Sporisorium ellisii is a parasitic species of fungus in the family Ustilaginaceae, a family of smut fungi, that infects various members of Andropogon, a widespread genus of perennial bunchgrasses.

[2] In plants infected by S. ellisii, the fungus often invades the reproductive structures, rendering them sterile.

[3] Species of Andropogon that are hosts for S. ellisii include: