The high phase content of inorganic dielectric fillings will give a strong electric driving force and hard matrix.That is a contradiction in enhancing the electro-deformation of dielectric elastomers(DEs).Therefore,in this paper,by focusing on how to approach a balance between these and finding an effective way to tune the electric response of the DEs,the theoretical calculation and experimental investigation based on calcium copper tita-nate(CCTO)/poly(dimethyl siloxane)(PDMS)were car-ried out.It is found that CCTO with a smaller particle size shows a larger dielectric parameter.With smaller CCTO particle as the fillings,the fabricated elastomer composite would approach to a low modulus by a proper CCTO phase morphology in the matrix.