  We report on the results from Suzaku observations of the Galactic black hole
X-ray binary H 1743-322 in the low/hard state during its outburst in 2012
October. We appropriately take into account the effects of dust-scattering to
accurately analyze the X-ray spectra. The time-averaged spectra in the 1-200
keV band are dominated by a hard power-law component of a photon index of
\approx 1.6 with a high-energy cutoff at \approx 60 keV, which is well
described with Comptonization of the disk emission by hot corona. We estimate
the inner disk radius from the multi-color disk component, and find that it is
1.3-2.3 times larger than the radius in the high/soft state. This suggests that
the standard disk was not extended to the innermost stable circular orbit. A
reflection component from the disk is detected with R = \Omega/2\pi \approx 0.6
(\Omega is the solid angle). We also successfully estimate the stable disk
component in a way independent of the time-averaged spectral modeling, by
analyzing short-term spectral variability on the \sim 1-sec timescale. A weak
low-frequency quasi-periodic oscillation (LF QPO) at 0.1-0.2 Hz is detected,
whose frequency is found to correlate with the X-ray luminosity and photon
index. This result may be explained by the evolution of the disk truncation
radius.
