An all-fiber waveplate made by a piece of birefringent photonic crystal fiber (PCF) is proposed and studied in this paper. The characteristics of the proposed waveplate, including the wavelength dependent phase difference between the orthogonal polarized propagation mode in the waveplate, and temperature stability of the waveplate, were investigated theoretically and experimentally for the first time to our knowledge. Compared with the fiber waveplate made by the stress induced or the conventional geometrical shape formed (such as the elliptical core fiber) birefringent fiber, the waveplate based on the birefringent PCF has distinguishable advantages including high temperature stability and large bandwidth. A prototype quarter-waveplate is fabricated by cutting and splicing a segment of birefringent PCF with conventional single mode fiber. The measurement showed that the fluctuation of the ellipticity of the output light from the waveplate can be kept within
0.23° for temperatures varying from 25°C to 200°C, and the bandwidth for ellipticity larger than 43° can be as large as 70 nm.