Flexible ferrocenyl-containing silicone rubbers (FSRs) with various ferrocenylsubstituted unit contents of 25, 50, and 75 mol.% were obtained by applying a simple method included catalytic hydrosilylation (between polymethylhydrosiloxane and vinylferrocene) and self-cross-linking reactions (dehydrocoupling between Si–H groups). Self-cross-linking is one of the most suitable and simple methods to coat and obtain FSRs on various contact conductive surfaces, such as onto ITO glass or ITOPET. The synthesized FSRs exhibit the electrochromic (EC) properties, resulting from the reduction-oxidation of ferrocenyl groups (Fc/Fc+ transformations at E0 c.a. 0.36 V) and leading to color change: oxidation causes new band formation at 634 nm in UV-vis
spectra. FSR with ferrocenyl-substituted unit content of 50 mol.% (FSR50) is the most optimal in terms of EC (coloration efficiency of 10.98 cm2·C–1, coloring and bleaching times of c.a. 49 and 66 s, which are close to undoped oligoaniline-functionalized polysiloxanes and carbazolyl-modified polysiloxanes) and mechanical properties (the tensile strength, Young’s modulus and elongation at break are 2.80 MPa, 25.33 MPa, and c.a. 50%, respectively). The previously reported EC polysiloxanes have lack of mechanical characteristics. Both electrochromism and flexibility predominantly make FSR50 promising materials for creation of flexible and stretchable EC devices.