With the rapid development of information technology, there is a growing demand for people in indoor location services.This paper proposes a novel high-precision indoor three-dimensional positioning algorithm for single light emitting diode (LED). By using three tilted photodetectors (PD)and one horizontal PD as receivers.Calculating the ratio of received optical power of the three tilted PDs to the horizontal PD respectively. According to the relationship of position between the PDs and the tilt angle, azimuth angle, placement angle of the tilted PD and other parameters, establish a mathematical relationship between the received optical power ratio and the receiver's three-dimensional coordinates, calculate the three-dimensional coordinates of the receiver at any position. The simulation results show that in the positioning area of 1 × 1 × 1.5 m3, when the inclination angle α is 25°, the azimuth angle difference θ is 90°, the placement angle ω1=0°, ω2=90°, ω3=180°, the distance r between the horizontal PD center and the tilted PD center is 1 cm, the positioning accuracy is better, the point with the positioning error within 3 cm accounts for 84 % of the total test points, and the average positioning error is 2.52 cm. Compared with the traditional indoor positioning technology, the cost of the positioning technology used in this paper is greatly reduced, the positioning accuracy is significantly improved,and can get three-dimensional coordinates.