With the development of technology and insight in the many different industrial sectors the variety of the products are increasing rapidly. That diversity requires different engineering solutions and those solutions require different composite materials with variable properties. Thus, composite materials are getting great interest due to the tailorable characteristics. Expandable polystyrene (EPS)/Glass/Epoxy composite is novel material type of random discontinuous and hybrid composite. The composite material specimen has been fabricated via vacuum infusion technique in a closed mold. EPS beads and chopped glasses were mixed and filled into the mold, afterwards epoxy resin was introduced into to the vacuumed mold. Thermogravimetric analyses of composite specimen and neat resin have been conducted between 25-600 oC with a heating rate of 10oC/min. The experimental results showed that main weight loss starts around 345 oC but the neat resin has a quite sharp loss after the loss started. But, composite specimen showed a decelerating model-like characteristic. The tangent lines revealed that composite specimen shows a lower thermal stability due to the EPS in the composite specimen. As a result even the slightly lower thermal stability of the composite, the peak limit of usage of EPS/Glass/Epoxy composite could be 120 oC before the major weight loss.