A series of HPW/Al2O3 solid acid catalyst with loading from 10% to 70% was synthesized. These catalysts were characterized by N2 adsorption-desorption, XRD, NH3-TPD, FT-IR spectroscopy and Py-IR spectroscopy. The above studies indicated that HPW kept its Keggin type structure in the loading range of 50%～70% .The catalysts had strong Brönsted acid and their total acidity increased with the laoding of HPW. The catalytic activity of these catalysts were evaluated by carrying out polymerization of tetrahydrofuran (THF).The results indicated that higher acidic catalyst led to the higher yield of PTMEG, yet the lower average molecular of PTMEG.