In this paper, we present the analysis of a deep (99.6 ks) observation of G304.6+0.1 with the X‐ray Imaging Spectrometer on board the Suzaku satellite. The X‐ray spectral data are well fitted with a plasma model consisting of a thermal component, in collisional ionization equilibrium, and a non‐thermal component. The thermal emission is well fitted with the vmekal model with an electron temperature of kTe∼ 0.75 keV, a high absorbing column density of NH∼ 3.9 × 1022 cm−2 and near/lower solar abundances, which indicate that the X‐ray emitting plasma of G304.6+0.1 is dominated by a swept‐up ambient medium. The non‐thermal component is well fitted with a power‐law model with a photon index of Γ∼ 1.4. We have found a relatively high electron density ne∼ 2.3f−1/2 cm−3, an age t∼ 1.4 × 104f1/2 yr and an X‐ray emitting mass Mx∼ 380f1/2 M⊙ at an adopted distance of d= 10 kpc. Using the morphological and spectral X‐ray data, we confirm that the remnant is a new member of the mixed‐morphology supernova remnants.