[en] In this thesis, we study various decay and production processes of charged Higgs bosons at the Large Hadron Collider (LHC) in the context of a general complex Minimal Supersymmetric Standard Model (MSSM) with minimal flavor violation. We investigate the effect of the complex phases of the soft supersymmetry breaking parameters and of the Higgsino mixing parameter, μ, on the decay widths and production rates. The CP violating asymmetries induced by those phases are also considered. The calculations are done at the one-loop level. This is nontrivial since there are a large number of Feynman diagrams and various types of singularities (UV divergences, soft and collinear singularities, threshold singularities). We discuss in detail our calculation method and how to handle those divergences. In particular, the topic of one-loop renormalization and neutral-Higgs mixing effects in the complex MSSM for processes involving Higgs bosons are addressed. The higher order corrections to the decay of charged Higgs bosons into aW-boson and the lightest neutral Higgs boson are calculated and shown to be significantly large. The CP asymmetry arising from all complex phases is considered, especially from the top-quark trilinear coupling, A_t, and μ, which induce a large contribution to the CP asymmetry. We perform a complete calculation of the next-to-leading order (NLO) electroweak (EW) corrections to the charged Higgs production in association with a W-boson via the bb annihilation channel and a consistent combination with other contributions including the standard and supersymmetric-QCD corrections and the gg fusion, with resummation of the leading radiative corrections to the bottom-Higgs couplings and the neutral Higgs-boson propagators. We observe a strong dependence of the production rates on the phases of A_t and of the gluino-mass parameter M₃ and a large CP asymmetry arising mainly from the gg fusion. The NLO EW corrections to the charged Higgs production in association with a top quark and a tagged bottom quark via gg fusion are calculated and shown to be still sizable even after subtracting the large tan β enhancement. The strong dependence of the NLO EW corrections on the phase of A_t is observed. Our studies show the importance of the higher order corrections to the decays and the productions of the charged Higgs bosons in the complex MSSM. For the searches of charged Higgs bosons at the LHC, those corrections should be taken into account when doing analysis.