(n-BrC6H4C2H4NH3)2PbBr4 (n-BrPhe) (n = 2, 3, 4) single crystals were synthesized with the aim of enhancing the scintillation light yield of (C6H5C2H4NH3)2PbBr4 (Phe), and their photoluminescence (PL) and scintillation characteristics were evaluated. In PL, a sharp peak due to the exciton emissions from the inorganic layer was observed at 390–420 nm in the n-BrPhe samples. They had lifetimes of 4.7 ns (2-BrPhe), 2.1 ns (3-BrPhe), and 0.9 ns (4-BrPhe) owing to the exciton recombination in the inorganic layer under 340 nm excitation. In scintillation, a sharp peak due to exciton emissions from the inorganic layer was detected at 410–440 nm under X-ray irradiation, and the decay time constants under X-ray irradiation were 2.3 ns (2-BrPhe), 2.0 ns (3-BrPhe), and 2.1 ns (4-BrPhe). Moreover, the scintillation light yields under gamma-ray irradiation from 241Am (59.5 keV) were found to be 3100 (2-BrPhe), 2200 (3-BrPhe), and 5900 photons/MeV (4-BrPhe), which were lower than that of Phe (18000 photons/MeV).