Let \(M_\theta =({\mathbb {R}} < imes {\mathbb {C}}^2, \underset{\theta }{\cdot }) \ (\theta \) an irrational number), be the Mautner group. We describe the \(C^*\)-algebra of \(M_\theta \) as a subalgebra of \(C_0({\mathbb {C}}^2,{\mathcal {B}}(L^{2}({\mathbb {R}}))) \)