Abstract The pyrolysis characteristics of GFRP (Glass Fiber Reinforced Plastic), which is a thermosetting plastic composed of glass fibers and polymer compounds, were determined under non-isothermal conditions while heating at 5–20 °C/min from 500 to 900 °C using a thermo-gravimetric analyzer (TGA) and a batch-type pyrolyzer. The kinetic parameters for the GFRP were derived from the Freedman method with resultant activation energy ranging from 41.4 kJ/mol to 78.4 kJ/mol. The main components of the product gases were carbon monoxide from the ether and carbonyl decomposition of polymer and hydrogen from the aromatic ring breakage. The structural variations in the GFRP char were determined using BET, SEM, and FT-IR techniques. The surface area of GFRP char exhibited its maximum value at 600 °C, decreasing at higher temperatures with the collapsing macro-pore structure. The decomposed portion of the polymers attached to the glass fiber increased when increasing the temperature from SEM image. These data are useful for understanding the GFRP pyrolysis and gasification processes.