Among Aharony et. al.' suggested a hole-induced frustration model to describe magnetic properties and the superconductivity of La2CuO4. In this model, before metallic phase is turned on, by doping nonmagnetic Sr^(2+) ions, there. will exist a spin-glass state. Doping nonmagnetic Cd^(2+) ions in a K2NiF4 type hvo-dimensional single crystal (C2H5NH3)2MnCl4, we found that, if the concentration of Cd between 0.1 to 0.2 of that of Mn, the Curie temperature will be increasing with more Cd. This anomalous behavior strongly suggests that there is a spin-glass state in (C2H5NH3)2Mn1-xCdxCl4.