In the title compound, C(16)H(12)FNO(3), the dihedral angle between the benzene ring and the plane of the indole ring system is 71.60 (6)°. In the crystal, mol-ecules stack along the b axis through π-π inter-actions between the adjacent indole-2,3-dione units with a centroid-centroid distance of 3.649 (3) Å. Inter-molecular C-H⋯O=C and C-H⋯π inter-actions further stabilize the structure, forming a three-dimensional framework.