In this study, a comprehensive structural analysis of the linear redox-active ferrocenyl-containing polysiloxanes (FPSs) was performed by the liquid-state 1H, 13C, and 29Si nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC), and cyclic voltammetry. FPSs with tunable Fc unit content ranging from 20 to 100 mol% were obtained by anionic ring-opening polymerization (AROP). The 29Si NMR spectroscopy indicates the successful anionic homopolymerization of the mono- and tetraferrocenyl-substituted cyclotetrasiloxanes (Fc4D4 and Fc1D4) by appearance of new signals of Si atoms corresponding to a polymer backbone. An analysis of pentad assignments in 29Si NMR determined the anionic copolymerization of Fc4D4 with D4 by indicating signals of neighboring Si atoms from different types of polymer units (DF and D), which differ from the signals of homopolymers. The Mayo-Lewis copolymerization constants of Fc4D4 and D4 were determined by the Fineman–Ross method. The molecular masses and unimodal molecular weight distribution of FPSs were estimated by using GPC. FPSs possess redox-activity. Thus, the proposed comprehensive approach analyzes structural features of the functional silicones with enhanced redox properties, which can be applied in (opto)electronics, coatings, and biomedicine.