This study investigates the effect of polymer and inorganic dielectric materials on pentacene-based cylindrical organic thin-film transistors (C-OTFT). The gate dielectric has a significant impact on the design of C-OTFT. We performed a comparative investigation using the 3D-Atlas numerical simulator to analyze the electrical characteristics of C-OTFT on various gate dielectric materials, such as inorganic dielectric (S i O2) and organic dielectrics (PVP, PI). Our research revealed that differences in the dielectric constant and material properties of the dielectric layer led to deviations in performance metrics like threshold voltage, I on / I off ratio, capacitance, mobility, and subthreshold voltage swing. After that, an investigation showed that SiO2, an inorganic dielectric, works at low voltage, while organic dielectric materials have the highest field effect mobility and a steep subthreshold slope. The comparative analysis reveals that CTFT, using organic as the gate dielectric, outperforms S i O2 in mobility, making it a promising candidate for e-textile applications.