This study mainly deals with cenosphere-filled phenolic resin-based composite that is prepared using ceramic-ceramic fiber as reinforcement by traditional hand layup technique. The effect of cenosphere at various percentage is investigated on the mechanical, ablative, and thermal properties of the filled composites. Mechanical investigation revealed that the addition of microsized cenosphere up to 10% concentration increased the tensile strength of the composite. It is also observed that the addition of cenosphere increased the compressive strength and impact resistance of the composites. Thermogravimetric analysis (TGA) and ablative test revealed that the addition of cenosphere not only decreased both linear and mass ablative rates but also increased the upper working temperature of the filled ceramic/phenolic composites. © 2015 Society of Plastics Engineers.