Silicon‐added and modulation‐doped higher manganese silicide (HMS, MnSi1.7) films have been prepared on glass substrates by magnetron‐sputtering of MnSi1.85, Si, and Al targets. Silicon‐addition and modulation‐doping are used to enhance the Seebeck coefficient and reduce the electrical resistivity, respectively. Raman spectra indicate that the silicon‐added MnSi1.7 film consists of two phases, crystalline MnSi1.7 and crystalline silicon. It is found that the silicon‐added MnSi1.7 film has a larger Seebeck coefficient (S), but a higher electrical resistivity (ρ) as well. Consequently, the thermoelectric power factor (PF = S2/ρ) is not enhanced, 0.320 × 10−3 W/m K2 at 733 K, and about the same as that of a pure MnSi1.7 film. The silicon‐added MnSi1.7 layer in a modulation‐doped structure Si:Al/MnSi1.7/glass, however, has a higher energy barrier height, a larger Seebeck coefficient, and a lower electrical resistivity. As a result, the thermoelectric power factor is greatly enhanced and can reach 0.573 × 10−3 W/m K2 at 733 K.