The operating principle and design criterion of fiber-optic parametric 2R (re-amplification, re-shaping) regenerator (FOPR) are described based on data-pump solutions. A FOPR is designed by simulation from degenerate four-wave mixing (FWM) pump bandwidth, wavelength configuration of the probe continuous wave, and power transfer function (PTF), and the necessity of using the power control unit in FOPRs to improve regenerator performance is also pointed out. Then, an all-optical 2R regenerator is developed and the experimental measurement for the regenerability is done. The measurement results show that, the PTF slope is about 1.7 with the extinction ratio (ER) improvement of about 5 dB, and the experimental data are consistent with the simulation results.