The quantum confinement Stark effect of three types of GaInNAs quantum wells, namely single square quantum well, stepped quantum wells and coupled quantum wells, is investigated using the band anti-crossing model. The comparison between experimental observation and modeling result validate the modeling process. The effects of the external electric field and localized N states on the quantized energy shifts of these three structures are compared and analyzed. The external electric field applied to the QW not only changes the potential profile but also modulates the localized N states, which causes band gap energy shifts and increase of electron effective mass.