Electrical actuators were made from films of triblock copolymers, poly(methyl methacrylate)-b-poly(n-butyl acrylate)-b-poly(methyl methacrylate). We used casting solvents to obtain different contents of lamellar structures. Lamellar phase morphologies were observed using transmission electron microscopy. The dielectric elastomer films with high nano-lamellar structures were coated on both sides with compliant electrode materials, producing small strains and slow voltage application velocities due to the higher elastic modulus and low dielectric constants. Dielectric elastomer films with lesser contents of nano-lamellar structures had higher dielectric constants, which resulted in larger and rapid deformations when voltages were applied. Deformation in nano-lamellar structured dielectric elastomer films is affected by the content of nano-lamellar structures, which affects the dielectric constants of the materials.