The synthesis and characterization of some novel cationic siloxanes copolymers containing quaternary ammonium salt (QAS) groups in the backbone is reported in this article. One cationic oligomer having QAS in the backbone and reactive groups like 2,3-epoxypropyl and 2-hydroxy-3-chloropropyl (RCO) as well as 1,3-bis(3-amino-propyl)tetramethyldisiloxane or alpha,omega-bis(3-aminopropyl)oligodimethylsiloxane (AP) were used as precursors for this goal. Elemental analysis, IR and H-1 NMR spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy were used to characterize the obtained copolymers. The thermal stability of the cationic siloxane copolymer increased when the siloxane oligomer having a high number of siloxane units in the chain (AP) was used as a precursor.