The wave propagation in a long pyroelectric cylinder of crystal class 6 with inner and outer irregular shape is considered. The frequency equation has been derived for the traction free, earth connected, and thermally insulated surfaces. The boundary conditions at the arbitrarily shaped boundaries are satisfied using the Fourier series expansion collocation method. The longitudinal and flexural vibrations of barium titanate ceramic, which belongs to the (6 mm) class, have been analyzed numerically. The numerical results in the case of elliptical and cardioidal cross sections with an elliptical cavity are tabulated and are presented graphically.