The adiabatic ionization threshold (AIT) of trans- and gauche-benzocaine has been measured by zero electronkinetic energy-pulsed field ionization (ZEKE-PFI) spectroscopy to be 7.8412 ± 0.0008 eV (lasers at 34134.4and 29109.3 cm-1) and 7.8421 ± 0.0004 eV (34144.8 + 29105.7 cm-1), respectively. AITs computed at theB3LYP/AUG-cc-p-VDZ level for the two conformers are some ∼2500 cm-1 lower than the experimental; incontrast their energy difference is very close. The trans-benzocaine cation ZEKE spectra has been recordedtaking a number of S1 intermediate vibronic states. The spectra provide an energy threshold for the appearanceof intramolecular vibrational redistribution (IVR) around ∼540 cm-1 in the S1 state.