The molecular structures of ground state and first single excited state for pyrazoline derivatives are optimized with DFT B3LYP method and ab initio “configuration interaction with single excitations”(CIS) method, respectively. The frontier molecular orbital characteristics have been analyzed systematically, and the electronic transition mechanism has been discussed. Electronic spectra are calculated by using TD-DFT method. These results are consistent with those from the experiment. The molecular structures of ground state and first single excited state for pyrazoline derivatives are optimized with DFT B3LYP method and ab initio “configuration interaction with single excitations” (CIS) method, respectively. The frontier molecular orbital characteristics have been analyzed systematically, and the electronic Transition spectra has been discussed. Electronic spectra are calculated by using TD-DFT method. These results are consistent with those from the experiment.