We found a nonlinear response in 1-100 ms region only when the liquid crystal was under the condition very close to the isotropic state. This must be the origin of the nonlinear optical response under "pretransitional state," observed by many researchers. This nonlinear optical response can be observed by changing either the pump intensity or temperature. This is not limited for the dye-doped liquid crystal, but applies to pure liquid crystal, too.