We propose a model to explain the W boson mass anomaly reported by the CDFII collaboration that would suggest new physics (NP). We introduce exotic fermions; one isospin doublet vector-like lepton, one isospin singlet singly-charged vector-like lepton, and an isospin doublet inert scalar. The proposed model provides sizable muon anomalous magnetic moment (muon g−2) due to no chiral suppression and nonzero mass difference between the real and imaginary parts of neutral inert scalar bosons. The inert scalar mass squared difference and vector-like exotic leptons (L′,E′ in the main text) affect oblique parameters. Especially, the T-parameter shift from zero explains the W boson mass anomaly. We search for the allowed parameter region to explain both muon g−2 and W boson mass anomaly at the same time. We also discuss a dark matter (DM) candidate assuming the real part of the inert scalar field to be the one. We find that lighter DM mass is favored to be consistent with experimental constraints.
