Enlightened by nonlinear property of the pseudo direction of arrivals (DOA) estimation, a rotary method by rotating the array is used to suppress ambiguity. By employing the multiple signal classical algorithm (MUSIC), the DOA is estimated before and after the rotation. Taking advantage of two estimations, a rotary MUSIC is defined to reduce the ambiguity, as well as the improved R-MUSIC. With simulations, it has been proved that the proposed rotary method have a great suppression of ambiguity. In comparison with traditional sparse array method of eliminating ambiguity, the proposed rotary method has greater ambiguity suppression and can work in a wider frequency band.