  The CP-violating effects are studied in the electron-positron annihilation to
produce $t\bar{t}$ pair within the Model-III of the two-Higgs-doublet
extensions, which allows flavor changing neutral currents via Higgs exchanges.
Complete analytical expressions for the form factors of the top quark electric
and weak dipole moment induced in the framework of the model are presented.
Several observables sensitive to the CP violation are calculated. The
dependences of the CP-violating effects on Higgs boson masses and the possible
phase angles are discussed. We find that the CP-violating observables can be of
the order of $10^{-4}$ in general but may reach to $10^{-3}$ for the most
favorable parameters in the model.
