We examine the possibility of small CP-violating supersymmetry (SUSY) phases in string-inspired supergravity models in which supersymmetry is broken by the auxiliary components of the dilaton and moduli. It is found that the SUSY phases can be suppressed by a small factor governing the breakdown of the approximate Peccei-Quinn symmetries nonlinearly realized for the moduli superfields that participate in supersymmetry breaking. In many cases, the symmetry breaking factors are exponentially small for moderately large values of the moduli, leading to small phase values in a natural way.