Abstract: The development of ferroelectric composites and the constitutive relations of ferroelectriccomposites are reviewed in this paper. The non-linear electromechanical coupling behaviors of theferroelectric composites induced by the ferroelectric and ferroelastic switching of ferroelectric phasesand the elastic, viscoelastic and dielectric properties of matrix are discussed. The consititutiverelations of ferroelectric composites are studied by means of micromechanics.