Beyond Standard Model Higgs Boson Physics \\ at the CMS Experiment

Searches for Beyond Standard Model (BSM) Higgs bosons at the CMS experiment are presented. The analyses are based on proton-proton collision data recorded by the CMS experiment at the LHC at CERN at 7~TeV and 8~TeV centre-of-mass energies in the years 2011 and 2012 respectively, corresponding to an integrated luminosity of up to 25~fb$^{-1}$. No evidence for additional Higgs bosons other than the 125~GeV standard model-like Higgs boson are found, and stringent exclusion limits are derived in different BSM scenarios.