The thermal conductivity of form-stable PEG/SiO2 phase change material (PCM) was enhanced by in situ doping of Al2O3 using an ultrasound-assisted sol-gel method. Fourier transform infrared spectroscopy (FT-IR) was used to characterize the structure, and the crystal performance was characterized by the X-ray diffraction (XRD). Differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA) were used to determine the thermal properties. The phase change enthalpy of PEG/SiO2-Al2O3 reached 124J g(-1), and thermal conductivity improved by 12.8% for 3.3 wt% Al2O3 in the PCM compared with PEG/SiO2. The hybrid PCM has excellent thermal stability and form-stable effects. Crown Copyright (C) 2014 Published by Elsevier B.V. All rights reserved.