Strong field ionization-photofragmentation (SFI-PF) with ultrafast pump-probe scheme is a powerful approach to study the dynamics of molecular cationic electronic states.Here we carry out a SFI-PF study on the cationic electronic states of vinyl bromide,C2H3Br.The yields of the parent C2H3Br+ and the formation of the fragment (Br+,C2H2+ and C2H3+) ions have been measured at different pump-probe delay time.Analysis provides experimental evidence of A2A\'-X2A\'\'intemal conversion of vinyl bromide cations which occurs in a time of about 220 fs,and the time of C2H3+formation induced by the dissociation of the A2A\'state around 300 fs.The study would add our knowledge of the behavior of electronic excited states of complex molecular cations.