Spectroscopic investigation of a dihydrogen bonded complex between phenol and borane-trimethylamine is reported here. Laser-induced fluorescence excitation, fluorescence detected infrared, and infrared-ultraviolet hole-burning spectroscopic studies were carried out in supersonic jets to investigate the complex formation between phenol and borane-trimethylamine. The redshift in the electronic transition and the low-frequency shift of the O-H stretching vibration established the proton donating ability of phenol in the complex. The experimental results together with the ab initio quantum mechanical calculations affirmed the formation of the dihydrogen bond in the complex.