A comprehensive investigation of molecular structure and electronic properties of bioactive 3,7-dinitrodibenzobromolium cation was carried out using ab initio calculation and IR and Raman spectroscopic studies. Geometric optimization of the 3,7-dinitrodibenzobromolium cation was performed using the restricted Hartree-Fock method with different basis sets. The resulting molecular structure agrees very well with X-ray diffraction data. Middle-infrared IR spectra and Raman spectra of the 3,7-dinitrodibenzobromolium bisulfate were obtained, and its fundamental vibrations were assigned and compared with the theoretical predictions. The agreement between the calculated and experimental frequencies is excellent, except for the symmetric and asymmetric vibration frequencies of the nitro group which show relatively larger discrepancies between the calculated and experimental results. This can be attributed to the neglect of the electron correlation in the HF method and neglect of the crystal packing force and counterion effects in the theoretical calculation.