An amorphous NiP/SiO2 aerogel catalyst, prepared by a sol-gel method, showed extremely high thermal stability up to 500 degrees C as determined by DSC. Its catalytic activity was also much higher than Ni/SiO2 and amorphous NiP/SiO2 (prepared by chemical deposition) catalysts far selective hydrogenation of cyclopentadiene to cyclopentene in a continuous flow fixed-bed reactor under atmospheric pressure at 150 degrees C. The experimental results were discussed according to the catalyst characterizations, including XRD, BET, oxygen uptake, EXAFS, and TEM.