The present paper presents the development of a process for the synthesis of low-priced and novel ceramic fibres. Currently, there are no commercially available ceramic fibres in the SiCO system despite previous patent applications for SiCO fibres. The incorporation of boron into the SiCO network via the synthesis of polyborosiloxanes and subsequent pyrolysis, the so-called polymer route, still remains a relatively unknown field. The cost saving factor constitutes the main advantage of this method compared with the conventional sol-gel synthesis. For this purpose, the structure, composition and spinning behaviour of self-developed, meltable polyborosiloxanes were investigated and characterized. Furthermore, the pyrolysis behaviour of the obtained polymers was investigated by means of thermogravimetric analysis. After pyrolysis, high resolution transmission electron microscopy, scanning electron microscopy and electron energy-loss spectroscopy were used for the analysis of the microstructure and nanochemistry of the obtained SiBCO ceramic products with the aim of determining a possible correlation between the applied precursors and crystallization behaviour of the obtained ceramics. Finally, rheological measurements were conducted to provide relevant information on the flow properties and spinning behaviour of synthesized polyborosiloxanes.