Abstract: Wind-up is one error source in GNSS positioning, but contains useful information about antenna spin rates. A novel method is proposed to estimate antenna spin rate based on single-difference-between-station wind-up effect. First, the starting and ending time of the antenna rotation is determined according to variation of geometry-free observations. Then, the antenna rotation angle can be estimated from geometry-free observations, the single-difference-between-station for single satellites, and the antenna spin rate can be obtained for a single satellite. The elevation-weighting method is used to get the final antenna spin rate. An experiment was designed, the results show that the antenna spin rate can be accurately estimated. Estimation of accuracy for the mean antenna rotation rate was about 0.5 degrees per second in the experiment.