Abstract. In this paper, we examine the dynamic anti-plane behavior of interacting redial cracks emanating from the edges of two interfacial circular cavities in piezoelectric bimaterials under incident anti-plane shearing wave (SH-wave). Green's functions for a semi-infinite piezoelectric medium with two circular cavities are determined by using complex variable method. The present problem is reduced to a series of Fredholm integral equations of the first kind based on Conjunction and crack-division techniques. Typical examples are provided to show the effect of the piezoelectric constants, structural geometry, and the wave frequencies of incident wave upon the local stress field around the crack tips.