We applied the two-color resonant two-photon ionization and mass-analyzed threshold ionization techniques to record the vibronic and cation spectra of 2,4-difluoroaniline. The cation spectra were recorded by ionizing via the 0 0 , X 1 , 6b 1 , and 1 1 levels of the electronically excited S 1 state. Most of the observed active modes of this molecule in the S 1 and cationic ground D 0 states are related to the in-plane ring deformation vibrations. The band origin of the S 1 ←S 0 electronic excitation was found to appear at 33294±2cm −1 , whereas the adiabatic ionization energy was determined to be 63935±5cm −1 . Comparing the data of 2,4-difluoroaniline with those of aniline, 2-fluoroaniline, and 4-fluoroaniline, one can learn the effects of fluorine substitution on the electronic transition and molecular vibration.