The dispersion analysis in a fluid filled and immersed thermo–electro elastic hollow cylinder composed of homogeneous, transversely isotropic material is studied within the frame work of linear theory of elasticity. The motions of the cylinder are formulated using the constitutive equations of a transversely isotropic piezo–thermo elastic material with a preferred material direction collinear with the longitudinal axis of the cylinder. The equations of motion of the internal and external fluids are formulated using the constitutive equations of an inviscid fluid. Displacement potentials are used to solve the equations of motion of the hollow cylinder and the fluids. The perfect–slip boundary condition is employed at the fluid–solid interface to find the frequency equation of the coupled system consisting of the cylinder, internal and external fluid. The non–dimensional frequencies obtained by the author are compared with the result of Paul and Raju [Paul, H. S., Raju, D. P, Asymptotic analysis of the modes of wave propagation in a piezoelectric solid cylinder. J. Acoust. Soc. Am. 71(2)( 1982) 255–263] which matches well and shows the exactness of the author’s method. The computed dimensionless frequency, phase velocity, attenuation, thermo mechanical coupling factor and specific loss are plotted in the form of dispersion curves for the material PZT-5A.