SiO2-riveted phosphotungstic acid (T-PWA-SiO2) was synthesized using the sol-gel method and thermally treated in a microwave synthesizer. The dissolving-detaching experiment shows that PWA in T-PWA-SiO2 exhibits better fastness than in the sample without thermal treatment (PWA-SiO2). The T-PWA-SiO2 samples were then combined with poly(2,5-benzimidazole) (ABPBI) to prepare ABPBI/(T-PWA-SiO2) composite membranes using the polyphosphoric acid direct-castingmethod. These composite membranes were characterized through X-ray diffraction and infrared spectroscopy. Then, the T-PWA-SiO2 particles were combined with ABPBI through hydrogen bonding between PWA and C = N in ABPBI. Membrane morphologies were investigated using scanning electron microscopy. Results of the thermogravimetric analysis indicate thermal stability of the composite membranes below 200 degrees C. The proton conductivity and durability between ABPBI/(T-PWA-SiO2) and ABPBI/(PWA-SiO2) composite membranes were also compared. The conductivity and life of the composite membranes were enhanced using T-PWA-SiO2. The conductivity of the ABPBI/(T-PWA-SiO2) (46 wt%) composite membrane was approximately 0.055 S/cm at 180 degrees C under 100% relative humidity.