We evaluated the effect of an amide compound bearing methyl groups on the properties of tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) cast films. The spontaneous electron transfer between N,N-dimethylacetamide (DMA) and the TCNQ complex is expected to change the casting condition. Then, we obtained a higher density of nanofibers in TTF-TCNQ films using DMA. The electrical conduction of TTF-TCNQ films using DMA was 58.0 S/cm, which is twice that of previously reported polycrystalline films. We measured the Seebeck coefficients of the films for their future possible use as thermoelectric materials. The Seebeck coefficient and power factor of the films prepared with DMA were 32.3 mu V/K and 6.05 mu W/mK2, respectively.