Abstract: A dual-elliptical-core polarization splitter based on photonic crystal fiber was proposed. The relationship between splitter length and structure parameters was analyzed using full vectorial finite element method. The variation rules of splitter length with hole pitch, duty circle and bridge were found for the given dual-elliptical-core polarization splitter. Results suggest that if the structure pattern was set, the shorter hole pitch is and the broader the bridge is, the shorter the splitter length is. Duty circle has noticeable influence on extinction ratio, but not on splitter length. According to these rules, an ultra-short dual-elliptical-core polarization splitter was optimized. The length of the polarization splitter is as short as 0.775 mm, extinction ratio reaches up to 50 dB with the wavelength of 1 550 nm, and the bandwidth is more than 30 nm when the extinction ratio more than 20 dB, which covers the communication C band from 1 535 nm to 1 565 nm.