The charged Higgs boson is an inevitable particle in supersymmetric models, both in the minimal version and in extensions. It is also a particle, which may have different decay channels depending on the scalar representations in the model, and thus it may help in identifying the model. In this talk I will consider the simplest singlet and triplet extensions of the minimal supersymmetric standard model, and in particular, describe some smoking gun signals of charged Higgs at the LHC collider. I will also comment the charged scalars in a supersymmetric left-right model.