In this article, submicron and micron calcium copper titanate (CCTO) crystallites with different morphologies were successfully designed and prepared by directly thermal treatment method and molten salt method, respectively. Then, the silicone elastomer filled with self‐prepared CCTO particles had high dieletric constant, low dielectric loss, and actuated strain which was greatly improved at low electric field. The dieletric constant at 50 Hz obviously increased from 2.15 for pure silicone elastomer to 4.37 and 4.18 for the submicron and micron CCTO/poly (dimethyl siloxane) (PDMS) composites. The dielectric loss of the composites retained at a low value (less than 0.06). Meanwhile, the elastic modulus of CCTO/PDMS composites was increased slightly only with a good flexibility. Compared to pure silicone elastomer (2.25%), the submicron and micron CCTO/PDMS composites with 2 wt % content exhibited a greater strain of 7.69% and 9.83% at a low electric field of 5 V/μm. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42613.