The ambiguity resolution is the key issue for global navigation satellite system (GNSS) high precision position. As the traditional three carrier ambiguity resolution (TCAR) method has shortcoming when solving the carrier ambiguity of single difference carrier phase measurement. A single difference carrier phase (SDCP) three carrier ambiguity resolution method was proposed by using the estimation of the relative position between two receiving antennas. It is illustrated by the test experiments that the success rate of SDCP ambiguity resolution with using the proposed algorithm is more than 98%; and the three-dimension(3D) position accuracy based on the ambiguity free SDCP measurements is about 58% higher than the position accuracy that using double differences carrier phase (DDCP) measurements.