Good quality single crystal of L-proline lithium bromide monohydrate (LPLBM) have been grown (size=15×6×5 mm³) for the first time by slow cooling technique. The crystal structure was confirmed by powder X-ray diffraction study and observed that the titled compound is crystallized in monoclinic system with space group P2₁. The lattice parameters were refined by CHECKCELL and POWDERX software’s and found to be in close agreement with the reported one. Fourier transforms Raman spectroscopy was done for the titled compound in the range of 5-3500 Cm^-1 and confirms its formation by observing the fundamental vibrational modes. The ultra violet-visible and near infrared absorption spectroscopy measurement was carried out which shows that the grown crystal is having very less absorbance and confirms its colorless nature. Optical transmission was calculated and reveal that the grown crystal is highly transparent i.e. 78 % in entire testing range. The titled compound was found to be of direct band gap category and its optical band gap was found to be ~5.71eV.