A single pump polarization-insensitive and widely tunable all-optical wavelength conversion for 10 Gbit/s non-return-to-zero (NRZ) signal is experimentally demonstrated by means of four-wave-mixing (FWM) in highly nonlinear photonic crystal fiber (PCF). The residual birefringence in the 50 m dispersion-flattened guarantees the FWM-based wavelength conversion to be polarization insensitive when the pump polarization is exactly at 45° to the birefringent axes of the PCF. Experimental results show that the polarization dependence of FWM in the PCF can be decreased to be less than 1 dB over 28 nm of wavelength tunable operation.The conversion efficiencies are better than -13 dB and the Q factor of idler signal is larger than 7 over the conversion range with signal polarization change.