  We investigate the confinement properties in the multi-instanton system,
where the size distribution is assumed to be $ \rho^{-5} $ for the large
instanton size $ \rho $. We find that the instanton vacuum gives the area law
behavior of the Wilson loop, which indicates existence of the linear confining
potential. In the multi-instanton system, the string tension increases
monotonously with the instanton density, and takes the standard value $ \sigma
\simeq 1 GeV/fm $ for the density $ (N/V)^{{1/4}} = 200 MeV $. Thus, instantons
directly relate to color confinement properties.
