The resonance enhanced multiphoton ionization/time-of-flight mass spectra of p-chlorophenol are studied by using a laser mass spectrometer with special designed heated sample inlet system. The REMPI excitation spectra(275～285nm)of the parent ion(4-CIP⁺)and the fragment ions(C_{<6/SUB>H5O⁺,C5H5Cl⁺,C6H(+,5),C5H(+,5),C4H(+,3),C3H(+,3)are acquired. It was shown that the excitation spectra from different fragment ions or the parent ion are found to have the similar spectra features due to the same intermediate state. The chlorophenol molecular is firstly one photon resonantly excited to the intermediate state,and then absorbs another photon to produce the parent ion(C6H5O⁺). In combination with the structure of p-chlorophenol in the S1 state and the power indexes of different fragment ions,the results indicate that fragment ions are produced from the parent ion through the ladder mechanism.}