The low-temperature specific heat of a superconductor Mo 3 Sb 7 with T c = 2.2 Β± 0.05 K has been measured in magnetic fields up to 5 T. In the normal state, the electronic specific heat coefficient c n , and the Debye temperature H D are found to be 34.5(2) mJ mol Γ1 K Γ2 and 283(5) K, respectively. The enhanced c n value is interpreted as due to a narrow Mo-4d band pinned at the Fermi level. The electronic specific heat in the superconducting state can be analyzed in terms a phenomenological two BCS-like gap model with the gap widths 2D 1 /k B T c = 4.0 and 2D 2 /k B T c = 2.5, and relative weights of the molar electronic heat coefficients c 1 /c n = 0.7 and c 2 /c n = 0.3. Some characteristic thermodynamic parameters for the studied superconductor, like the specific heat jump at T c , DC(T c )/ c n T c , the electron-phonon coupling constant, k eΓph , the upper H c2 and thermodynamic critical H c0 fields, the penetration depth k, coherence length n and the Ginzburg-Landau parameter j are evaluated. The estimated values of parameters such as 2D 0 /k B T c , DC(T c )/c n T c , N(E F ) and k eΓph suggest that Mo 3 Sb 7 belongs to an intermediate-coupling regime. The electronic band structure calculations indicate that the density of states near the Fermi level is formed mainly by the Mo-4d orbitals and that there is no overlap between the Mo-4d and Sb-sp orbitals.