Using the effective medium approximation, we set up a model for the investigation of 3-phase magnetoelectric composites of 0-0-3 connectivity. The two particulate phases are magnetostrictive particles and piezoelectric particles, which are considered to be spherical in shape and dispersed in a continuous polymer matrix of non-negligible electrical conductivity. The electric, magnetic and elastic properties of the constituents are assumed to be isotropic. We calculate the magnetoelectric voltage/charge coefficient of the composites as a function of bias magnetic field and compare the theoretical results with measurements on Terfenol-D/PZT/LiClO 4 -PEO and Terfenol-D/PZT/PEO 0-0-3 composite systems. Reasonably good agreement between model predictions and experimental results is obtained.