The basic design principle of a pin-cushion two-dimensional position sensitive detector (PSD)――Gear′s theorem is testified, and the position formula of this type of PSD is derived. Moreover, presented in this paper are the fabrication process and device performance of the pin-cushion PSD. The pin-cushion PSD devices (sensitive area 8 mm×8 mm) fabricated with IC technology show good optoelectronic properties, excellent position linearity and accuracy. The dark current is 15 nA when the reverse bias is 5 V. The peak sensitivity is over 0.6 A/W. Within 75% sensitive area, the measured RMS of position error is about 0.135 mm, and its nonlinearity characterized with RMS of position error is around 1.1%, almost improved by one order of magnitude compared with that of the tetra-lateral two-dimensional PSD.