In the title mol-ecule, C(16)H(15)FN(4)O, the dihedral angle between the fluoro-substituted benzene ring and the pyrimidinone ring is 52.34 (7)°, while the dihedral angle between the fused benzene ring and the pyrimidinone ring is 3.30 (6)°. An intra-molecular N-H⋯N hydrogen bond may, in part, influence the conformation of the mol-ecule. In the crystal structure, inter-molecular N-H⋯N hydrogen bonds and weak C-H⋯π(arene) inter-actions link pairs of mol-ecules into centrosymmetric dimers.