In this work, a boundary element method (BEM) is applied for time-harmonic analysis of three-dimensional linear piezoelectric solids. Coupled frequency domain boundary value problems of the linear theory of piezoelectricity are considered assuming zero initial conditions, in the absence of the body forces and free electric charges. The elastic and electric variables are combined into the extended vectors and tensors. Proposed boundary element approach employs regularized weakly singular frequency domain boundary integral equations (BIEs) for the extended displacements. A standard collocation procedure for the mixed boundary elements is used. Integral expressions of the three-dimensional frequency domain dynamic piezoelectric fundamental solutions are employed. Results of the boundary-element analysis of a test problem are provided to validate the proposed BEM formulation.