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We have studied Cen A (NGC 5128) in the X-ray band (3–20 keV) and soft γ-ray band (40–600 keV) with the Large Area Counter (LAC) of the Ginga satellite (1989 March and 1990 February) and with a balloon-borne low background detector (Welcome-1, 1991 November), respectively. The observed continuous spectra show a power-law shape (Γ∼ 1.8) with relatively heavy absorption (NH ∼ 1.5 × 1023 H cm−2) at the low-energy end and a possible break at ∼ 180 keV. We analyzed the total spectra as the sum of the direct power-law flux from the central engine, the Compton-scattered flux from a cold cloud near to the engine, and the iron fluorescence-line flux. By assuming that the geometry around the central engine remained unchanged during the two-year period, we studied two possible cold cloud geometries by comparing Monte-Carlo simulations with our observations: the first is the Compton-reflection model in which the cloud forms a slab covering 2π sr behind the central engine, the second is a case where the central source is totally surrounded by a cold cloud. We found that the latter geometry reproduces our data well; the observed power-law spectrum is then identified as direct flux from the central engine which undergoes a break at ∼ 180 keV.