This talk forcus on the inverse scattering problems with phaseless far field data. To break the translation invariance of the phaseless far field data, we insert a point source or a point like scatterer in the scattering system. Such an technique makes it possible to retrieval the phase of the far field data. Thus the classical mehthods with full far field patterns can be applied for the inverse scattering problems. Some open problems will be mentioned.